64 ON THE MALE REPRODUCTIVE 



In what way tlie mature spermatozoids are produced from 

 the above-described motile, stellate cells, I have found it im- 

 possible to observe. Notwithstanding that I have examined 

 capsules of all sizes, I have never noticed any transition forms. 

 The next highest globules always contained spermatozoids, 

 differing from those in a state of complete maturity only in 

 their having a somewhat larger body. In their movements 

 they were precisely alike. 



Whether a stellate cell divide into several spermatozoids or 

 not, must be left undecided. In the Crustacea, we are also 

 unacquainted with the metamorphoses of tfie stellate cells, not 

 knowing even whether in any case they become motile sper- 

 matozoids. Dromia Iiumj)hii^ according to Kolliker, is the 

 only Crustacean in which, together with stellate cells, bodies 

 resembling filamentary spermatozoids are also found ; but 

 these were immotile. 



The further change which takes place in the spermatic 

 capsule for the evacuation of its contents is precisely like that 

 which occurs in the female capsule for the development and 

 expulsion of the embryos. When the spermatic capsule con- 

 tains mature spermatozoids in the uppermost globules, the 

 highest of those bodies breaks through the inembrane by 

 which the capsule is closed, and the envelope of the globule, 

 which in the mean while had increased somewhat in thick- 

 ness, represents a rounded sacculus placed upon a peduncle, 

 and the surface of which opposite to the peduncle is furnished 

 with a bundle of tentacular appendages. The peduncle en- 

 closes a continuation of the general nutritive substance, which 

 at this time projects only for a very short distance into the 

 spermatozoid-globule. The tentacles exhibit a slight degree 

 of motility, inasmuch as they are capable of a slow extension 

 and contraction ; but they have no urticating organs, and are 

 certainly wholly incompetent for the prehension of nutriment. 

 Nor at first do they serve for the occlusion of an opening 

 which is not formed till some time afterwards, when the very 

 thin membrane in which the spermatozoids are still specially 

 enclosed is ruptured. No movement of the entire envelope 

 is ever observable. 



Between the inner surface of this envelope and the mass of 

 spermatozoids there is a space filled with active spermatozoids, 

 when the membrane by which they are immediately enclosed 

 is ruptured or bursts spontaneously. But the spermatozoids 

 do not at once escape externally, as would necessarily be the 

 case had an opening previously existed at the place where the 

 tentacles are situated ; and it is not until the outer envelope 

 is also ruptured by stronger pressure that the spermatic ele- 

 ments are dispersed in the water. 



