SPERMATOGENESIS OF AMERICAN CRAYP'ISII 



NATHAN FASTEN 



PLATE 9 



1^ 



82 



ft % 



*>• 



86. 



J 





83 



87 



.S'"^\ 



84 





88t :^- 



Wk*»^H% 



d5 



i 



So. 



N. Fasten, photo. 



.<JCv 



91 



^"^ 



92 



647 



