1903.] The Acquirement of Secondary Sexual, Characters. 5o 



expert to determine their sex : examination, moreover, of the testicles 

 removed from cockerels subjected to the combined castration-vasotomy 

 just referred to, as well as of those removed from birds of the same 

 brood, showed that no spermatogenesis had arisen at the age selected 

 for operation. We may adduce examples in order to give the full 

 grounds for the general statement set forth with regard to these 

 experiments. 



Double Vasotomy. — Impure " Plymouth Rock," 7 — 8 weeks old. 

 Nine months after the operation the head was male in type ; neck- 

 hackles well developed ; tail beginning to assume male characters ; 

 spurs indicated. Twelve months after the date of operation the spurs 

 were stout, though short ; head thoroughly male ; neck- and saddle- 

 hackles moderately well developed ; tail short, male in kind, with 

 sickle feathers. 



The bird remained in the same condition, and was killed 12 months 

 after the date of the operation. At the autopsy, the testicles were 

 found to be of full size (about that of a pigeon's egg), and in their 

 general aspect quite normal. In connection with the right there was a 

 spermatocele about as large as a haricot bean ; this, on being punctured, 

 gave exit to a whitish fluid which microscopically showed numerous 

 spermatozoa, some of them motile. The superior segment of the 

 divided vas, or that in connection with the testicle, was dilated ; the 

 upper end of the lower segment was traceable into scar tissue in which 

 it terminated. On the left side there was no spermatocele in connection 

 with the gland, but the tubuli of the epididymis were abnormally 

 evident. On each side the noose of the silk ligature was found in situ 

 on the upper segment of the vas, above the level of the lower border 

 of the testicle. 



As a second instance we may recount the following : — 



Double Vasotomy. — " Plymouth Rock," about 8 weeks old. In the 

 summer of the year following the operation the head and neck-hackles 

 were typically male, saddle-hackles fairly so ; tail short, carried almost 

 vertically, contained a number of short curved feathers ; spurs short 

 and stout. In the winter of the same year the neck- and saddle- 

 hackles were typically male ; tail short, bushy, feathers curved ; spurs 

 long and sharp. The bird was killed in the spring of the following 

 year. Dissection showed the left testicle to be of full size, 4 cm. in 

 longer diameter ; in connection with the upper end of the epididymis 

 is a retention cyst filled with white secretion, and about 1 cm. in 

 diameter; the epididymis is, as a whole, enlarged from distension. 

 The upper end of the lower segment of the vas terminates a short 

 distance above the lower border of the testicle. The ligature lies in 

 situ on the end of the epididymal segment of the vas, which is separated 

 by a distinct interval from the other. 



The right testicle is slightly smaller than the left, the epididymis 



