43 



along in their development than those In the other end. 



g. The spermatogonia! nuclei lie in a oommon cytoplasmic 

 mass and multiply irregularly without the formation of a 

 spireme. A spireme and synapsis occur in connection with the 

 first miotic division. The second miotic division follows 

 soon after the first. 



4. In the mature sperm, the protoplasmic portion, con- 

 taining the nucleus, is cup- shaped. Prom the rim of the cup 

 peeudopodia project out like the rays of a star. There Is 

 a capsule half imhedded in the cup. An inturned tubule is 

 connected with an opening in the distal portion of the cap- 

 sular wall and a rod-like central hody arises from the prox- 

 imal side of the capsule and projects into the inner tuhule. 



5. In the transformation of the spermatid, the nucleus 

 becomes uniform in consistency, reduced in size and cup-shaped. 

 A mitochrondrial ring is formed between the nucleus and the 

 capsule. The capsule arises as a vacuole in the cytoplasm. In 

 the course of its development it shows an increasing affinity 

 for nuclear steins. 



6. The central body develops from a granule that appears 

 on the proximal side of the capsule. The inner tubule is 

 formed from two vesicles that arise at the distal end of the 

 central body. 



7. Hypotonic solutions of various salts and possibly 

 other stimuli cause a lengthening of the central body, an 

 eversion of the inner tubule and an inversion of the wall 

 of the capsule. 



8. When the sperms come in contact with the egg under 



