25 



A quite satisfactory method is to stain from two to five minutes in 

 a saturated aqueous solution of methyl green, with the application 

 of gentle heat. The heat may be applied by warming the slide over 

 a gas tiame as it steams, or by placing the jar containing the stain 

 in a hot water bath. The slide is then washed thoroughly and 

 eounterstained for five minutes in a strong aqueous solution of 

 eosin. This is a fairly reliable method, and many excellent pre- 

 parations may be obtained by its use. The nucleus is stained 

 green, the anterior part of the head and all of the tail pink. So 

 far, I have found this a very reliable stain for routine work. 



Pathology 



In the genital tracts that I have studied, a complete pathological 

 and bacteriological examination was made Avherever possible, but 

 in man}' of the abattoir animals, and certain others, gross and 

 microscopical examinations only could be made. The genital 

 organs of one hundred and ninety-six males have been examined, 

 and the gross or miscroseopical changes, or both, determined. The 

 abattoir animals Avere from a large slaughter house, and a small 

 local plant. 



Of the tracts, the pathology of which was studied, two were 

 from aborted fetuses ; seven from apparently normal young calves ; 

 four from mature fertile bulls ; and sixteen from mature infertile 

 or sterile sires. The remainder (167) of those examined were 

 from abattoir animals. Besides these, three specimens of seminal 

 vesicles, and seven of testes were studied. 



The tracts of the aborted fetuses and veal calves were apparently 

 normal, both on gross and microscopic examination of the vesicles 

 and testes. On gross examination, the tracts of the mature fertile 

 bulls were normal, except for the presence of many fine connective 

 tissue tufts and strands upon the serous covering of the tails of 

 the epidid>Tnes, and adjacent portion of the parietal layer of the 

 tunica vaginalis. jMicroscopic sections of all parts were apparently 

 normal. The more important pathological changes in the tracts of 

 the sixteen sterile or infertile bulls are given in the appended 

 chart. The tracts are numbered the same as in Group VI of the 

 report of the bacteriological findings ; that is, any particular num- 

 ber in either tal)le refei's to the same animal. Eeferences are made 

 throughout the text to some cases which appear in this group of 

 animals. Prostate and Cowper's glands are not included in the 

 chart as they were not examined in some, and were negative in the 

 others. Fibrous tufts and strands were present on the covering 

 of the epididymes in each animal. 



The study of sections from the abattoir animals, as well as those 

 from the sterile or infertile bulls, forms the basis for the follow- 

 ing observations upon the pathologA' of the male genital tract. 

 The tracts secured from the abattoir were studied for the most 

 part on the ba.sis of the organ rather than on that of the animal. 

 For example, all sections of testes were placed in the same bottle 

 of fixer, and the same plan followed for the other organs. 



