16 



4. There also seems to be a relatively long resting 

 stage after the nucleus of the spermatid Is formed hefore the 

 transformation Into the sperm heglns. 



6. In the transformation of the spermatid, three struc- 

 tures must he considered, viz., the nucleus, the capsule and 

 the mitochondrial ring. 



^. The nucleus becomes uniform In consistency, reduced 

 In size and cup-shaped. 



7^» The capsule arises In the cytoplasm as a clear 

 vacuole which may be stained V7lth Llohtgrun. Its content is 

 gradually changed to have a greater affinity for chromatin. 



8,. Prom a granule on the proximal side of the capsule 

 the central body develops Into the capsule. At the distal 

 end of this body a vesicle arises, which is changed into the 

 inner tubule. 



9. The mitochondrial substance is segregated from the 

 cytoplasm and deposited as a ring between the nucleus and 

 the capsule. 



Some of the theoretical questions connected with the 

 development and structure of the sperms of the decapods will 

 be taken up at the end of this article. At this point I wish 

 to say that the above description Is in agreement with the 

 principal observations made by Grobben '78, Gllson '86, Saba- 

 tler '93, Brandes '97 and Koltzoff '06. These authors have 

 all seen the same general structures and transformations. 

 They all describe a nucleus which during development Is modi- 

 fied in its staining reactions, reduced in size and often 

 flattened or otherwise changed in its shape. They do not dis- 



