Pequi, Caryocar brasiliense, é uma das espécies de destaqueno bioma do cerrado brasileiro, devido a sua utilização na medicina, na culinária popular, indústria em geral, e na do ferro e do aço. Na região de São José do Xingu (MT), uma árvore de pequi sem espinho no endocarpo foi encontrado e isso permite melhorar pequi não só para o consumo, aproveitando a alta apreciação que já possui. Para detectar as diferenças existentes entre o genoma de pequi com e sem espinho no endocarpo, marcadores moleculares RAPD foram utilizados. Os polimorfismos gerados foram clonados e sequenciados, a fim de identificar as sequências responsáveis pela alteração fenotípica. Observou-se que o pequi sem espinho é geneticamente isolado de outras populações de pequi com espinho no endocarpo, provando que essa característica está relacionada com a divergência genética da espécie. Análise em Blastn evidenciou a similaridade dos genes Dof1 e com o gene da fosfinotricina-acetiltransferase de Z. mays. Na análise da BLASTx, a similaridade foi verificada com as proteínas responsáveis pela deficiência de ferro 4 redutase e catalase.

Caryocar brasiliense (pequi), is one of the main species at the biome of the Brazilian savannah due to its use in culinary, popular medicine, industry in general, and iron and steel industry. At São José do Xingu (MT), a tree of C. brasiliense without thorn at the endocarp was found, which enables the improvement of C. brasiliense not only for consumption but also to the high appreciation it already has. To detect the existing differences between the pequi with and without the thorn at the endocarp, RADP markers were used. The generated polymorphisms were cloned and sequenced in order to identify the sequences that are responsible for the fenotypical alteration. It was observed that the pequi without thorn is genetically isolated from the other populations of pequi with thorn at the endocarp, proving that this characteristic is related to the genetic divergence of the species. Analysis in BLASTn evidenced the similarity of the Dof1 genes of Zea mays to its gene of phosphinotricin acetyl transferase. In the analysis of BLASTx, the similarity was verified to the proteins responsible for the deficiency in ferric reductase 4, and catalase.

The wing Somatic Mutation and Recombination Test (SMART) in D. melanogaster was used to study genotoxicity of the medicinal plant Tabebuia impetiginosa. Lapachol (naphthoquinone) and β-lapachone (quinone) are the two main chemical constituents of T. impetiginosa. These compounds have several biological properties. They induce apoptosis by generating oxygen-reactive species, thereby inhibiting topoisomerases (I and II) or inducing other enzymes dependent on NAD(P)H:quinone oxidoreductase 1, thus affecting cell cycle checkpoints. The SMART was used in the standard (ST) version, which has normal levels of cytochrome P450 (CYP) enzymes, to check the direct action of this compound, and in the high bioactivation (HB) version, which has a high constitutive level of CYP enzymes, to check for indirect action in three different T. impetiginosa concentrations (10%, 20% or 40% w/w). It was observed that T. impetiginosa alone did not modify the spontaneous frequencies of mutant spots in either cross. The negative results observed prompted us to study this phytotherapeuticum in association with the reference mutagen doxorubicin (DXR). In co-treated series, T. impetiginosa was toxic in both crosses at higher concentration, whereas in the HB cross, it induced a considerable potentiating effect (from ~24.0 to ~95.0%) on DXR genotoxity. Therefore, further research is needed to determine the possible risks associated with the exposure of living organisms to this complex mixture.

Nesse estudo nós usamos a técnica de Differential Display Reverse Transcriptase - Polymerase Chain Reaction (DDRT-PCR) para comparamos o perfil de mRNA em Melipona scutellaris durante o desenvolvimento ontogenético pós-embrionário e em operárias adultas, rainha natural e induzida pelo Hormônio Juvenil III. Fragmentos diferencialmente expressos foram detectados usando as seguintes combinações de primers: HT11G-AP05; HT11C-AP05; HT11G-OPF12; HT11G-OPA16. Dos 9 ESTs descrito nesse trabalho, 6 tiveram expressão diferencial nas fases de larva L1 e L2, sugerindo serem mecanismos chave no regulação do desenvolvimento larval em Melipona. A combinação HT11G-AP05 revelou em L1 e L2 um produto com similaridade à proteína tioredoxina redutase de Clostridium sporogenes, uma proteína importante durante os processos de oxidoredução. Esse estudo representa as primeiras evidências moleculares do perfil de expressão durante o desenvolvimento ontogenético em abelhas do gênero Melipona.

We have compared gene expression, using the Differential Display Reverse Transcriptase - Polymerase Chain Reaction (DDRT-PCR) technique, by means of mRNA profile in Melipona scutellaris during ontogenetic postembryonic development, in adult worker, and in both Natural and Juvenile Hormone III-induced adult queen. Six, out of the nine ESTs described here, presented differentially expressed in the phases L1 or L2, or even in both of them, suggesting that key mechanisms to the development of Melipona scutellaris are regulated in these stages. The combination HT11G-AP05 revealed in L1 and L2 a product which matches to thioredoxin reductase protein domain in the Clostridium sporogenes, an important protein during cellular oxidoreduction processes. This study represents the first molecular evidence of differential gene expression profiles toward a description of the genetic developmental traits in the genus Melipona.

The anatomy of the internal organs of the male reproductive apparatus (MRA) of adults and pupae was compared among 51 species of bees, including representatives of six families. Four different types of MRA were found. The type I is present in males of the less derived families (Colletidae, Andrenidae, and Halictidae) and is characterized by three seminiferous tubules per testis, which are almost completely enveloped by the scrotal membrane. The type II is an intermediary between types III and I and is present in Melittidae and Megachilidae, as well as in some Apidae studied, being characterized by post-vesicular deferent ducts outside the scrotal membrane and by three or four seminiferous tubules per testis, except for Apis mellifera L., which has a secondarily increased number of tubules. Type III was only found in the Apidae studied and is characterized by separately encapsulated testes and genital ducts (except for the post-vesicular deferent duct). Accessory glands are well developed, and the ejaculatory duct is thickened with fissures in its wall, which may also occur in the type II. Type IV is present exclusively in the tribe Meliponini, and is characterized by the absence of accessory glands.

A anatomia dos órgãos internos do aparelho reprodutor de machos (ARM) adultos e pupas foi comparada em 51 espécies de abelhas, incluindo representantes de seis famílias. Foram obtidos quatro tipos diferentes de ARM. O tipo I está presente em machos das famílias mais basais (Colletidae, Andrenidae e Halictidae) e é caracterizado por três túbulos seminíferos por testículo, o qual é quase totalmente envolvido pela membrana escrotal. O tipo II é um tipo intermediário entre os tipos I e III e está presente em Mellitidae e Megachilidae, como também em alguns Apidae estudados, sendo caracterizado por possuir dutos deferentes pós-vesiculares fora da membrana escrotal e possuir três ou quatro túbulos seminíferos por testículo, exceto Apis mellifera L., a qual possui secundariamente um número aumentado de túbulos. O tipo III foi achado somente nos Apidae estudados e é caracterizado por apresentar os testículos e dutos genitais (exceto o duto deferente pós-vesicular) encapsulados separadamente, as glândulas acessórias são bem desenvolvidas e o duto ejaculador é calibroso, apresentando fissuras em sua parede externa, as quais podem ocorrer também no tipo II. O tipo IV está presente exclusivamente na tribo Meliponini e é caracterizado pela ausência de glândulas acessórias.

Este trabalho teve como objetivo estabelecer metodologias adequadas para o isolamento e inoculação de Septoria lactucae e avaliação de nove cultivares de alface (Lactuca sativa), Vitória-de-Santo-Antão, Uberlândia 10.000, Maioba, Elba, Aurélia, Black Seeded Simpson, Grand Rapids, Salad Bowl-Mimosa e Babá de Verão, quanto aos níveis de resistência à septoriose, em condições de casa de vegetação e campo. Os melhores resultados obtidos foram: a) para isolamento: transferência dos cirros de conídios diretamente para o meio de BDA com os antibióticos estreptomicina, cloranfenicol, ampicilina e rifampicilina; b) para inoculação: aspersão das plantas no estádio de seis a oito folhas com a suspensão de inóculo na concentração de 1 x 10(4)conídios/ml, e manutenção em câmara úmida por 48 h. Houve diferenças significativas entre as cultivares testadas em casa de vegetação e em campo. Tanto em casa de vegetação quanto em teste de campo as cultivares Maioba e Vitória de Santo Antão foram avaliadas como a mais susceptível e a mais resistente, respectivamente. Diante desses resultados, a metodologia de casa de vegetação pode ser considerada como altamente promissora para a avaliação rápida de grande número de variedades ou materiais genéticos, nos trabalhos de melhoramento de alface para a resistência à S. lactucae.

The objectives of this work were to establish appropriate methodologies for isolation and inoculation of Septoria lactucae in order to evaluate resistance. Nine lettuce (Lactuca sativa) cultivars (Vitória-de-Santo-Antão, Uberlândia 10.000, Maioba, Elba, Aurélia, Black Seeded Simpson, Grand, Rapids, Salad Bowl-Mimosa and Babá de Verão) were screened for resistance to this pathogen under greenhouse and field conditions. The best results obtained were: a) for isolation: to transfer cirrus of conidia directly to the surface of Petri dishes with PDA medium plus antibiotics (streptomycin, chloramphenicol, ampicilim and riphampicin); b) for inoculation: to spray plants of six to eight leaves with a conidia suspension of 1 x 10(4) spores/ml and keep them in a moist chamber for 48 h. Significant differences were found among cultivars both in greenhouse and field tests. Under both conditions the cultivars Maioba and Vitoria de Santo Antão were found to be, respectively, the most susceptible and the most resistant cultivars among those tested. From these results, the greenhouse test methodology is seen to ge highly promising for the rapid screening of a great number of genotypes in breeding programs of lettuce resistant to S. lactucae.

The number of xo alleles of a population of stingless bees can be estimated by observing the male proportion of the first brood comb produced by a new queen (about 40 Fl bees) and the total number of colonies. A proportion of 50% diploid males indicates insemination of the queen by a single male with some xo sex allele: 25% diploid male would indicate insemination by two males (one with some xo as the queen and another with different one). Diploidy was confirmed by cytology of the testis. The original population (78 colonies) of Ribeirão Preto, State S. Paulo, Brazil, had 8 xo sex alleles. From this population, 10 colonies were orphaned and taken to the Serra do Mar (Sea Mountains) at Espirito Santo State (1200 km far) in order that the virgin queen of each colony would cross with males of this region. Ten days after the nine hives (one was lost) were brought back to Ribeirão Preto. No one of them produced diploid males. New samples took from all the Meliponary revealed that the number of xo sex alleles to have increased to 17,3. Than, this methodology can be used to increase the genetic variability of the stingless bees populations.

Junça (Cyperus esculentus Linné), edible bulb of Maranhão that has good nutritional value. F. Marx, and W. E. Kerr.Bulbs of junça one sold in the streets oF Sao Luis, Ma, Brazil, as a delicacy. It has good nutritional value like: 6-10% protein, 6.95 to 9,32mg/lOOg of alpha-tocoferol, 1.20 to 2.52mg/100 of gama-tocoferol, 424.4mg/100g of K and 3,5mg/100g of Zn.Our samples had 1.4% glicose and 16.0% of saccharose. Literature is revised and this bulb is recommended for human consumption.

Seis isoenzimas de esterase foram estudadas durante o desenvolvimento de Anopheles darlingi usando eletroforese em gel de poliacrilamida e dois substratos diferentes, a-naftilacetato e a-naftliproprlonato. Esterases 5 e 6 foram detectados em todos os estágios do desenvolvimento, esterases 1 e 2 foram coradas com maior intensidade em larva, enquanto esterases 3 e 4 foram melhor visualizadas em pupa e adulto. Foram observadas grandes diferenças na intensidade de algumas isoenzimas durante o estágio de pupa,Quatro das seis isoenzimas revelaram variações na mobilidade eletroforética. A esterase 1 foi a escolhida para estudos genéticos, em virtude de ter sido a isoenzima que apresentou melhor coloração no gel. Dois alelos codominantes (Est 2*S e Est 2*F) codificam para este sistema polimórfico, com a freqüência de Est*S igual a 0,521. A distribuição fenotipica está de acordo com o esperado em Hardy - Weinberg.

Six esterase isozymes were studied during the development of Anopheles darlingi by using polyacrylamide gel electrophoresis and two different substrates, a-naphthylcelate and a-naphthylpropionate. Esterases 5 and 6'were detected in all developmental stages esterases 1 and 2 were more intensively stained if larvae, while esterases 3 and 4 were better visualized in pupae and adults. Strong differences in intensity of some of the isozymes were observed during the pupal stage.Four out of the six isozymes showed variation in the electrophoretic mobility. Esterase-2 was choosed for genetic studies, because was the best stained isozyme in the gels. Two codominant alleles {Est2*S and Est2*F) code for this polymorphic system, with the Est*S frequency equal to 0.521. Phenotypic distribution is in agreement with hardy-Weinberg expectations.

Resumo Os estudos de laboratório sobre a biologia de A. darling demonstraram que o ciclo biológico de ovo a adulto se faz, em média, em 15,6 dias e com uma taxa de sobrevivência de 57% quando criados de 25 a 28°C. O número médio de ovos por postura foi de 110±50,61 e eclodiram em média 83,31±48,21, com um tempo médio para eclosão de dois dias. O tempo de desenvolvimento de cada estádio imaturo apresentou variações. O 2.° e 3.° estádios larvais apresentaram um tempo de desenvolvimento menor do que o 1.° e 4° estádios.

Summary Laboratory studies about the biological cycle of Anopheles Darlingi showed that de development from egg to adult is completed in 15.6 days in average, and that the survival rate (from 25 to 28°C) was 57%. The mean number of eggs per female was 110±50,61 and the eclosion rate 83,31±48,21. Mean eclosion time was estimated in about 2 days. Data regarding the larval and pupal development are also showed.

Resumo Analisa-se o néctar de 302 abelhas de Melipona seminigra merrillae Cock. e 302 de abelhas de Melipona rufiventris paraensis Ducke, durante o período de maio de 1977 a abril de 1978, em Manaus. Do total de amostras estudadas de M. seminigra e M. rufiventris, 16 (5,3%) e 11 (3,6%) respectivamente, não continham pólen. Das 286 restantes (94,7%) de M. seminigra, 80 (28%) apresentavam pólen de uma só espécie, 88 (30,8%) de duas espécies e 118 (41,2%) de três ou mais. De 291 (96,4%) restantes de M. rufiventris, 33 (11,3%) apresentavam pólen de uma só espécie, 54 (18,6%) de duas espécies e 204 (70,1%) de três ou mais. Os grãos de pólen encontrados nas amostras de néctar representam ao todo 60 tipos morfológicos, distribuídos em 29 famílias, pelo menos 42 gêneros diferentes, dos quais 39 foram separados ao nível de espécie. Sugere-se que a maior porcentagem de visitas, a mais de uma espécie de plantas nectaríferas (72%) do que a plantas políníferas (39%), seja devida a estratégias das plantas unissexuais para obrigar a abelha visitar plantas masculinas para pólen na manhã e femininas para néctar mais tarde.

Summary During a period of one year samples of bee nectar from 302 Melipona seminigra merrillae Cock, and 302 Melipona rufiventris paraensis Ducke from Manaus (22-27) per month) were examined. Sixteen (5,3%) samples from M. seminigra and 11 (3,6%) samples from M. rufiventris did not contain any pollen. Of the 286 (94,7%) remaining samples of M. seminigra, 80 (20%) had one type of pollen, 88 (30,8%) had two, and 118 (41,2%) had 3 or more different types. Of the 291 (96,4%) remaining samples from M. rufiventris, 33 (11,3%) had pollen of a single species of plant, 54 (18.6%) had two, and 204 (70,1%) of three or more different types. A total of 60 different types of pollen from 29 families, 42 genera, and 39 species of plants were recognized. It is suggested that the greater frequency of visits to more than one species in nectariferous flowers (72%) than to polliniferous ones (39%) is due to strategies developed in order to make the bees visit male flowers for pollen and later the females, for nectar.

Summary INPA is developing studies concerning the agricultural plants of the Brazilian Indians. a collection was made among the Kayapó Indians of the Cupa vine (Cissus gongylodes Burch. ex Baker, Vitaceae). This note provides botanical information on this plant, its uses by the seringueiros (rubber collectors) and by the indians, and agronomical and chemical data.

This paper deals with problems on population genetics in Hymenoptera and particularly in social Apidae. 1) The studies on populations of Hymenoptera were made according to the two basic types of reproduction: endogamy and panmixia. The populations of social Apinae have a mixed method of reproduction with higher percentage of panmixia and a lower of endogamy. This is shown by the following a) males can enter any hive in swarming time; b) males of Meliponini are expelled from hives which does not need them, and thus, are forced to look for some other place; c) Meliponini males were seen powdering themselves with pollen, thus becoming more acceptable in any other hive. The panmixia is not complete owing to the fact that the density of the breeding population as very low, even in the more frequent species as low as about 2 females and 160 males per reproductive area. We adopted as selection values (or survival indices) the expressions according to Brieger (1948,1950) which may be summarised as follows; a population: p2AA + ²pq Aa + q2aa became after selection: x p2AA + 2pq Aa + z q²aa. For alge-braics facilities Brieger divided the three selective values by y giving thus: x/y p2 AA + y/y 2 pq Aa + z/y q²aa. He called x/y of RA and z/y of Ra, that are survival or selective index, calculated in relation to the heterozyg

Material: Studies were made mainly with Ascaris megalocephála Cloq. univalens and bivalens, and also with Tityus bahiensis Perty. 1) Somatic pairing of heterochromatic regions. The heterochromatic ends of the somatic chromosomes in Ascaris show a very strong tendency for unspecifical somatic pairing which may occur between parts of different chromosomes (Figs. 1, 2, 3, 7, 10, 11, 12, 13, 14, 16, 18,), between the two ends of the same chromosome either directly (Figs. 4, 5, 7, 8, 11, 12, 13, 15, 16, 17, 18) or inversely (Fig. 8, in the arrow) and also within a same chromosomal arm (Fig. 6). 2) During the early first cleavage division the chomosomes are an isodiametric cylinder (Figs. 6, 9, 11, 13, 14). But in later metaphase the ends become club shaped (Figs. 1, 2, 3, 4, 5, 7, 10) which is interpreted as the beginning of migration of chromatic substance from the central euchromatic region towards the heterochromatic regions. This migration becomes more and accentuated in anaphase (Figs. 19, 22, 23) and in the vegetative cells where euchromatic region looses more and more staing power, especially in the intersititial zones between the individual small spherical chromosomes into which the euchromatic region desintegrates. The emigrated chromatin material is finally eliminated with the heterochromatic chromosome ends (Fig. 23 and 24). 3) It seems a general rule that during mitotic anaphase all chromosomes with diffuse or multiple spindle fiber attachement (Ascaris, Tityus, Luzula, Steatococcus, Homoptera and Heteroptera in general) move to the poles in the form of an U with precedence of the chromosomal ends. In Ascaris, the heterocromatic regions are pulled passively towards the poles and only the euchromatic central portion may be U-shaped (Fig. 19, 22, 25). While in the other species this U-shape is perfect since the beginning of anaphase, giving the impression that movement towards the poles begins at both ends of a chromosome simultaneously, this is not the case in Ascaris. There the euchromatic region is at first U-shaped, passing then to form a straight or zig-zag line and becoming again U-shaped during late anaphase. This is explained by the fact that the ends of the euchromatic regions have to pull the weight of the passive heterochromatic portions. 4) While it is generally accepted that, during first meio-tic division untill second anaphase, all attachement regions remain either undivided or at least united closely, this is not the case in chromosomes with diffused or multiple attachment. Here one clearly sees in all cases so far studied four parallel chromatids at first metaphase. In Luzula and Tityus (for Tityus all figs. 26 to 31) this division is allready quite clear in paraphase (pro-metaphase) and it cannot be said wether in other species the division in sister chromatids is allready present, but not visible at this stage. During first anaphase the sister chromatids of Titbits remain more or less in contact, while in Luzula and especially in Ascaris they are quite separated. Thus one can count in late anaphase or telophase of Ascaris megalocephala bivalens, nearly allways, four separate chromosomes near each pole, or a total of eight chromatids per division figure (Figs. 35, 36, 37, 38, 39, 40, 41).

1° - Cita-sé a evolução das abelhas segundo MICÍÍENÉR" (1944). 2.° - A evolução dos Melíponíneos é estudada sob o ponto de vista da sua biologia, estabelecendo-se o tipo do meliponíneo primitivo. 3.° - São feitas considerações sobre a distribuição geográfica dos meliponíneos, entrando-se em detalhes sobre os seus fosseis, sobre a influência dos deslocamentos geológicos do cenozoico sobre sua distribuição, com particular referência ao seu estabelecimento na América do Sul. Considera-se também o e$eito das glaciações e a descontinuidade por ela provocada na distribuição dos meliponíneos. 4.° - São feitas hipóteses sobre a época em que se formaram as Meliponas, sobre o processo de determinação das castas e sua influência na evolução das mesmas. O tipo M. marginata é considerado o mais primitivo dos existentes atualmente. É dada uma hipótese, baseada na biologia e genética das Meliponas, para explicar sua evolução a partir de uma Trígona primitiva. 5.° - Sugere-se que a M. fascisrfta (excluidas a M. punc-ticollis e M. concinnula, que necessitam de estudos) seja do tipo da Meliponatrifatorial primitiva, tomando-se por base a sua proximidade a M. marginata, sua distribuição e sua variação. 6.° - Sugere-se como centro de origem das Meliponas a Bacia Amazônica, por ser esse lugar a zona onde há maior variação e por ser o centro geográfico da área habitada pelas Meliponas.

Studies on the genus Melipona 1 - Introduction and acknowledgements. 2 - Systematica. Three modern trends in the systematics of the Meliponini are cited: Ducke (1916), Schwarz (1932) and Moure (1946); The 14 species known of the genus Meliponaare given. 3 - Contribution to the Biology. There are three castes in Melipona: drones, workers and queens, which are easily distinguished on account of the differences in size, color, proportions and behavior. While the queen of Apis emerges in a state of sufficient development to be fertilized and to begin the laying of eggs, the queen of Melipona, on the other side, in a glance seems undernourished, get having received the same food as the workers, both in quantity and in quality. They emerge with undeveloped ovaries and, only after the fertilized queen is dead or too old, virgin queens may be fertilized and begin to be fed by workers. After 15 to 30 days, according to the number of workers and the food gathered, the queen begins to lay eggs. The queens, drones and workers emerge from cells of the same size and with more or less the same quantity of food. Variations of the quantity of food do not change the caste, but only the size of the bee. The caste determination in Trigonai (another genus of Meliponini) depends evidently upon differences in nutrition. It is easily seen that the cells which furnish drones and workers are different in size, though equal in form, from those from which emerge the queens. Somie data concerning the biology of the Meliponini are given below: 1st - The number of eggs laid by a queen: Melipona quadrifasciata anthiodioides - in 44 days (July 9th to Aug. 22nd - 1946) 590 eggs, with an average of 13 eggs per day, and a maximum of 22 eggs per day. Trígona (Plebéia) mosquito, (Mirim-guassú) - from July 9th to July 24th 1946, 249 eggs. Prom Aug. 9th to Aug. 24th, 1946 laid 1035 eggs; with an average of 69 eggs per day and a maximum of 120 eggs. 2nd) - A table is given showing the percentage of drones observed in the total of individuals in samples of brood combs. (See Quadro I and Quadro EE). 3rd) - The duration of the several phases in the lives of the Meliponaworkers and queens is: Phases Worker Queen Hatching of the egg 4,5 to 6,5 days 4,5 to 6,5 days Larva 7 to 8 days 7 to 8 days Prepupa 5 to 5,5 days 4,5 to 5 days Pupa 15,5 to 18 days 11,5 to 15 days Total, from egg to imago 34 to 37 days 30 to 34 days It is mentioned that the Meliponini constructs large honey and pollen pots of characteristic size, and form both In natural hives and in experimental colonies in wooden boxes. The workers in weak colonies of M. Marginata and M. schencki produce little wax, and excepcionally, use brood cells for storage Instead of pots, showing that their reactions are very variable. Other details of the brood cell, such as brood cells disposition, construction, destruction, etc., are discussed. 4 - Anatomy of the reprodutive organs. The sexual organs of the male consist of: a) Two testicles envolved by a thin membrane, each of the testicles formed by four testicular tubes, b) two vasa deferentia, c) two vesiculae seminales, which are spherical and very small, d) one ejaculatory duct and e) the pente. There are no accessory glands as in Apis and Bombus. (BORDAS, 1895) See Fig. 6 and 46). The reprodutive organs of the female consist of: a) two ovaries, each formed by four ovardoles. The length of these pvarioles is: 1,7 to 2,0 mms. in the worker or sterile female, 11,1 to 11,5 mms. in the virgin queen and 76 mms. in the fecundated queen (measures taken on Meliponafasciata melano ven ter), b) two oviducts, c) vagina and d) spermatheca with a pair of glands. This same description is applied to Trígona and Bombus, varying the proportions. 5 - Citology Studies on the cytology of the genera Melipona and Trigona were carried out Ovaries òf the pupas queens and workers, testicles of prepupas and young pupas of drones, brains and other somatic' ttisues of larvae were examined. The details of the technique and the results are given. ;The somatic tissue of the females, both queens and workers, presents 18 chromosomes. The spermatogeneáfó is normal, following the type described for Apis by Meves (1907) with expulsion of a cytoplasmatic Bud in the first division, and a nucleated bud in the second, The sperfiuatogonia and spermatids show 9 chromosomes. 'Polyploid c cel|sl and tissues are fre'quent, even in the testicles but polyploid secondary spermatocytes do not go through a second meiotic division. No polyploid individuals have been found às yet. The number of chromosomes is the same in all Melipona, studied: M. fasciata, M. marginata, M scheneki. M. quadrifasciata, A. e. 18 in the female and 19 in the male. 6 - Determination cf castes of queen and worker. There are many papers discussing the problem of caste determination in the social insects (Bibliography in the papers of Light, 1943 and Wheeler, 1928)* Two,, theoriescome always under discussion: a) the. Blasjtógezüc or; genptypJc determination and b) the Trophogenfè or somatogenic one. In the first case, special genes are supposed to be responsible while in the second case the determination is by means of food or other environmental factors. No one doubts today that the caste of .males In Hyme-hoptera is genetically determined by arrhenotoky, wjth very few exceptional casss. The Meliponabees do not escape this rule, as shown by chromosome counts. The opinions aré however divided with regard to the female castes.