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not possible that all the atypical vesicles arise from the medullary 
cords but that also a great number originates in such egg-balls. I 
said already before that egg-cells are found in the medullary cords 
in embryos and also in newly-born infants. The fact that the medul- 
lary cords and the egg-nests originate from the same epithelium, 
explains this phenomenon sufficiently’). But all the investigators 
have found that those cords afterwards break up into primary follicles. 
ScuMattz calls the eggcells, occurring in the medullary cords, 
strayed (verirrte) elements and supposes that they are reduced after- 
wards. In the case of dog, cat and other animals, in which the 
medullary cords remain, ScHMALTz does not mention the occurrence 
of eggcells in those cords or their metamorphosis into vesicles. 
The vesicle formation described before, I did not find mentioned 
anywhere, not even in the texi-books of pathological anatomy. 
Probably ScHorrLAENDER (Archiv. f. mikrosk. Anatomie, 1893) 
found the same thing in man, as described before, but he explains 
them differently. There is only one text-book of histology (the anti- 
quated book by Bönm and Daviporr) which, according to the 
representation of ScHOTTLAENDER, tells something more of the atypical 
vesicles than the other text-books I consulted. 
ScHOTTLAENDER distinguishes ‘‘Kiballenfollikel” and “Sehlauch- 
follikel”. He calls the follicles, reproduced in fig. 2 and 3 eggball- 
follicles and those reproduced in fig. 1e and fig. 4 “‘Schlauchfollikel”. 
According to him the origin of eggballfollicles is due to the fact 
that the eggballs are not broken up into primary follicles, owing to 
insufficient development of the connective tissue. 
He thinks that the ‘‘Schlauchfollikel” develop from the tubes of 
Priiicur made free. (In his opinion the “Pflügersche Schläuche” are 
flattened and elongated eggballs). Undoubtedly ScnorrLAENDER has 
seen in the human ovary vesicles, which were more or less modified 
cords and he described about the same phenomenon I saw. In the 
atypical follicles of fig. 4 and 1c however, I cannot see tubes of 
Pricer, made free, partly because they do not occur in man 
according to Bünrer, KerBer and Marr) and partly, because the 
investigation has taught us, that they are parts of epithelial strands, 
which undoubtedly must be looked upon as medullary cords. 
Like SCHOTTLAENDER, I should prefer to distinguish two types of 
atypical vesicles: viz. ‘“‘ballfollicles’ and ‘“cordfollicles”. Probably, 
they both originate, owing to an insufficient anlage and develop- 
1) It must nol be left unmentioned that vAN DEN BROEK (1895) thinks there is 
a connection between the medullary cords and the mesonephros and GIANNELLI 
(1915) thinks they originate in the stroma ovaril. 
