SEX STUDIES. XI 25 
Smith and Thomas, and a gynondromorph pheasant described 
by Bond in 1914. The oviduct is an almost constant feature in 
these birds. The only bird without an oviduct is one described 
in Brandt’s paper. Shattock and Seligmann’s Leghorn had two 
oviducts. Five of Brandt’s birds had abnormal oviducts, either 
anterior or posterior end being closed. In the rest, the female 
ducts were normal, just as in the birds described in this paper. 
In most of these papers, nothing is said about the vasa def- 
erentia. Brandt shows one picture of sections through two 
persistent Wolffian ducts, the one on the right side being larger 
than the one on the left. In the bird which he claims is a male 
with female characters developed, he says there are no vasa 
deferentia. Pearl and Curtis’s bird 16 had an oviduct on the 
left for the ovary, and a vas on the right for the testis. Shattock 
and Seligmann’s bird had two vasa. 
In comparing the structure of the reproductive organs, there 
again seems to be a preponderance of female over male. Four 
of Brandt’s birds had ovaries in more or less embryonic or de- 
generate condition. The four mule pheasants of Smith and 
Thomas had ovaries composed of stroma and interstitial cells, 
with no oocytes. Nos. 1427, 1425 and 1428 of our birds belong 
to this type. One of Brandt’s birds and 1429 of this paper 
had normal ovaries with oocytes. An ovotestis or mixed gland 
was present in two of Brandt’s birds, in Shattock’s Leghorn, 
in Bond’s pheasant, and in Atwood’s Hermaphrodite, 1349, and 
the Michigan bird of the present study. No. 1426 and Pearl 
and Curtis’s bird No. 16 both had an ovary on the left and a 
testis on the right, with the difference that while in both, the 
ovaries were inactive, the testis in 1426 was active and that in 
16 was not. One bird described by Brandt had two testes, one 
on each side. Hammond Smith is also quoted by Bond as 
describing three birds with some female secondary sex char- 
acters with normal testes present. In most of these birds, 
previously described, the gonad of whichever sex showed no 
signs of activity of the germ cells The first of Brandt’s birds 
is the one possible exception on the female side. Several of 
the birds in this study, however, show signs of past or present 
