4G4 



M. Louise Nichols. 



l>ecame invaginated or surroimded in an amniotic fashion by the 

 capsule. The latter then disintegrated, leaving as the mature 

 spermatozoon only the nucleus, processes and "acrosome." Koltzoff, 

 however, by his careful and detailed study of the structure and 

 behavior of the spermatozoa has shown very conclusively that this 

 method of homologizing the parts of the spermatozoon is consonant 

 neither with comparative morphology nor with the behavior of the 

 spermatozoon in fertilization. 



One of the most unique and puzzling features of the Decapod 

 spermatozoon is its lack of motility. The observations which Kolt- 

 zoff was able to make on the method of fertilization throw some light 



♦ 



Text-Figures 1-12. 



Comparative morphology of Crustacean Spermatozoa (somewhat diagram- 

 matic). 



1, Polyphemus ; 2, Cirripedia ; 3, Amphipoda ; 4, Isopoda ; 5, Mysis ; 0, 

 Squilla ; 7, Carididae ; 8, Anomura ; 9, Anomura ; 10, Homarus ; 11, Astacus ; 

 12, Brachyura, 



on this subject. An examination of a mixture of the eggs and 

 spermatozoa of Galathea revealed the fact that the spermatozoa are 

 carried passively by a stream of water to the surface of the egg. 

 When a protoplasmic process touches the surface of the egg it 

 becomes firmly attached. The rest of the spermatozoon continues to 

 sway back and forth until the other processes are brought in contact 



