25 



everslon Is probably marked by the funnel-Bhaped portion In 

 Pig. 76. The portion of the everted wall, derived from the 

 part of the tubnle turned by this second everslon is Indicat- 

 ed by the granule g. Pig. 77. At this stage there Is another 

 pause while the out turned part continues to swell. 



Finally the tension becomes so great that another portion 

 of the inner tubule is everted and as it turns the wall of the 

 capsule is also turned through the collar formed in the early 

 stage of the process of everslon. This last everslon is 

 shown halfway completed in Pig. 80, and the completed process 

 In Pig. 81. In the latter figure the central body stands on 

 the apex of the everslon and the inverted capsule inv.c. is 

 above the collar r. In dilute solutions of the salts used, 

 the protoplasmic portion which contains the nucleus and mi- 

 tochrondrlfld substance swells up to a spherical body as shown 

 in Pig. 82. Often one finds on the slides, bodies like the 

 one represented in Pig. 83. It is evident that these are ex- 

 ploded sperms from which the everted inner tubule has dis- 

 appeared leaving the central body, c.b.; the inverted capsule, 

 Inv.v. ; the collar, r; and the shrunken nuclear cup, n.c. 



4. Changes i n the central body. 



We shall now return to a more complete consideration of 

 the behavior of the central body and the part that it plays 

 in the explosion of the sperm. These sperms are so very small 

 it is difficult in many cases to distinguish the central body, 

 especially in the live unstained material. Some significant 

 facts however have been observed. As is shown in Pig. 61, 



