RELATING TO SECONDARY SEXUAL CHARACTERS. 39 



as they are present in all three." That the relative amounts of the 

 latter or their activity might still be accountable for the difference 

 would not seem entirely excluded from the evidence so far as it is given. 



A fourth hermaphrodite (Dexter's) laid 12 eggs and had a large 

 coiled oviduct. There was present "a large, lobulated reproductive 

 organ on the left," which proved to be an ovotestis. Several ovarian 

 tumors were present and there was testicular tissue. 



It is fairly evident, then, that four of these birds described by Boring 

 and Pearl were females with abnormal ovaries. The incomplete 

 development of the latter, or their abnormal condition due to tumors, 

 may sufficiently explain the occurrence of male secondary sexual 

 characters. That these tumors affect, to different degrees, such charac- 

 ters is expected from what is shown by imperfectly spayed females of 

 normal breeds. 



There are a few statements in the summary of this paper that call for 

 comment. The statement that the " development of comb, spurs, 

 and wattles does not stand in direct quantitative relation to the sex 

 of the gonad," appears to be only intended as a statement of fact based 

 on the author's observation. But in what sense is there an expectation 

 that they should stand in such relation beyond the obvious fact that 

 in the cock the comb and wattles are larger than in the hen, and that 

 spurs are generally present only on the cock. But if the expression 

 "sex of the gonad" implies the germ-cells it is not at all certain that 

 there is any expectation of a quantitative relation, and there is some 

 probability at least that other cells than the sex-cells are involved in 

 the development of combs, wattles, and possibly spurs. A castrated 

 cock has a small comb resembling that of the female bird. On the 

 other hand, removal of the ovary sometimes leads to an increase in the 

 comb and wattles. Here we have, to say the least, a paradoxical 

 situation, for the result looks superficially as though something in the 

 ovary keeps down the hen's comb, while something in the testes keeps 

 up the cock's comb, yet when the ovary is removed the hen develops 

 a cock's comb; when the testes are removed the cock develops a hen's 

 comb. The real meaning is, I think, that the genetic complex for 

 femaleness (one Z or else ZW) stands in itself for a full-sized comb, 

 while the genetic complex for maleness (two Z's) stands in itself for 

 small comb. 



Boring and Pearl state that " body-shape and carriage have a genetic 

 relation to the sex of the gonad." This statement means, I think, 

 that the amount of testicular matter present stands in some direct 

 relation to the shape of the body and carriage of the male. Castration, 

 both of the normal cock and the Sebright, seems to change the carri- 

 age somewhat and perhaps the shape. Both lose something of the 

 peculiar attitude of the male, but I have not been able to my own 



