The authors observing "Leptospira icterohaemorrhagiae's culture 11 and 12 months old, maintened in culture medium of Verwoort, modified found interesting aspects evidenced in the eletronic microscope. The authors noticed bodies of leptospira with condensation zones of cytoplasm assuming granular aspec (micrographs 1, 3, 4, 7, 9 and 12). In the micrographs 6 and 7 we see clearly one of these granules dismembering of the leptospira body whose image looks like that of other granules in the micrographs. We saw, in some conditions of experience, as in micrograph 3, that the above referred granules have 2 different aspects: one that isn't transparent and with irregular shape, looking like condensed chromatin and the other which has an irregular shape too, but is transparent, as if it had lost part of its primitive contents (micrographs 5. 7 and 13. In micrograph 2 we see one frequent aspect in works of this kind like that of CZEKALWSKI, J. W. and EAVES G., the granule formation with segmentation following it. As was said above a culture with this aspect was inoculated into guinea pigs whose hemoculture supplied again the germ isolated which guided us to the idea that these granules are a phase in the vital cycle of the leptospira or elements which can mantain condition and factors necessary to the continuity of the species.