HARRIS : DIMORPHISM OF CAMBARUS. , 57 



No. 21. C. immunis. F. I. About two or two and one-half inches 

 long. March 19, 1901. 



All lobes of testis sectioned. Proximal ends made up of emptied follicles. 

 Beyond these are some still containing apparently the original number of sper- 

 matozoa of the preceding season. A few follicles are filled with large primary 

 spermatogonia. An occasional follicsle contains spermatocytes in fine spireme 

 condition. Those of the distal end contain spermatogonia, among which an oc- 

 casional division figure is to be seen. The vas deferens is well filled with sperma- 

 tozoa. 



No. 22. C. immunis, F. I. Two and one-third or three inches 

 long. March 19, 1901. 



Two lobes and vas deferens sectioned. Is in practically same condition as 

 No. 21. 



No. 23. C. immunis. F. I. About two and one-half inches long. 

 March 22, 1900. 



Two anterior lobes and vas deferens sectioned. Condition practically same as 

 in No. 21. 



No. 24. C. immunis. F.I. About three inches long. March 22, 

 1901. 



Vas deferens examined. Well filled with spermatozoa. 



No. 25. C. hnniunis. F. I. About two and one-half inches long. 

 March 24, 1901. 



Somewhat broken up in preparation. Condition about same as No. 21. Sper- 

 matocytes not common. Follicles do not contain so many spermatozoa. 



No. 26. C. immunis. F. I. About two and one-fourth inches 

 long. March 27, 1901. 



Two lobes sectioned. Condition largely same as No. 21. No spermatocytes 

 were noticed and no follicles still containing any considerable number of sper- 

 matozoa. Spermatogonial region more extensive than in No. 21. 



No. 27. C. immunis. F. I. Early May, 1900. 



Sections rather poor. Lobe seems to be made up of the proximal area of emp- 

 tied follicles and a large distal area of spermatogonia, among which occasional 

 division figures are to be observed. The vas deferens is well filled with sperma- 

 tozoa. 



No. 28. C. imnmnis. F. II. April, 1900. 



Sections poor. Conditions practically same as in No. 27. Vas deferens weU 

 filled with spermatozoa. 



No. 29. C. virilis. F. II. May 5, 1900. 



Sections poor. Conditions probably much the same as in Nos. 27 and 28. 



No. 30. C. virilis. F. II. May 5, 1900. 



Condition largely same as the three preceding. In Nos. 27 to 30, taken in the 

 spring of 1900, we find essentially the same conditions, both in C. inwiun'iK and 

 C. virilis, as those observed in No. 21. 



