294 J- E. WODSEDALEK. 



what lower temperatures, the material showed little or no modi- 

 fications. When Bouin's fluid was modified, the alteration took 

 the form of the addition of a small amount of chromic acid, or 

 urea, or the reduction of the percentage of acetic acid. All 

 of these slight modifications gave very good results in the 

 testicular material, and the ovarian, embryological and foetal 

 tissues appeared to be best when fixed in the fluid modified with 

 chromic acid. The cold method (Hance '17) was also tried in 

 two instances with the testicular tissue but with less success. 

 And while I have not tried this out on the cattle tissue myself, 

 I have every assurance that the laboratory technician carried 

 out the process with great care. 



In the study of the male germ cells, smears as well as sections 

 were used. Many stains and counter stains were tried. Iron- 

 haematoxylin when used alone was found to be the most satis- 

 factory. All of the figures represented in this paper were made 

 from material stained in this manner. 



III. GENERAL ARRANGEMENT OF THE MALE GERMINAL CELLS. 



The structure of the testes of the bull is similar to that of the 

 other well-known mammals and bears a great resemblance to the 

 conditions found in the testes of the horse (Wodsedalek '14). 

 The interstitial cells as in the horse are small and fewer in number 

 in comparison with their large size and great abundance in the 

 testes of the pig. The size of the seminiferous tubules, as well 

 as the general size of the various germinal cells, however, corre- 

 sponds to the condition found in the pig. The usual types of 

 cells, (i) spermatogonia, (2) primary spermatocytes, (3) second- 

 ary spermatocytes, (4) spermatids, and (5) spermatozoa in 

 various stages of development, are present in great abundance. 



IV. SPERMATOGENESIS. 



In general the spermatogenesis of the bull corresponds to that 

 of the pig and the horse. Since many of the finer cytological 

 points are given in detail in the papers on the pig and the horse 

 (Wodsedalek '13 and '14) they are omitted here to avoid un- 

 necessary duplication. And while all of the finer details involved 

 in a thorough piece of work in spermatogenesis were carefully 



