i SS3 . ] Brewster on a Collection of Arizona Birds. 2 I 
statement is thus worded on account of the doubt connected with 
many of the descriptions. There are, however, three cases re- 
ported as occurring in hens which are comparable. The first 
case, that reported by Bechstein,* was a chicken with a testicle 
on the right side and an ovary on the left, that is much like the 
Pipilo. The two cases reported by Simpson f were less perfect. 
One was simply a female bird with a half developed vas deferens 
on the right side, the other had a vas deferens on each side. In 
both cases there were slight mixtures in the habits and plumage 
of the two sexes. 
In the Pipilo each side was perfect after its sex and showed 
no resemblance to the other sex, thus separating it from the second 
example given by Simpson. The natural explanation is that the 
two generative mounds took on the two sexes and that the acces- 
sory structures followed the master organs. So the Wolffian duct 
remained on one side and the Mullerian on the other. 
ON A COLLECTION OF BIRDS LATELY MADE 
BY MR. F. STEPHENS IN ARIZONA. 
BY WILLIAM BREWSTER. 
{Concluded from Vol. VII, ft. 212 .) 
122. Antrostomus nuttalli ( Aud.) Cass. Nuttall’s Whip- 
poor-will. — Although these Whip-poor-wills were common in 
many of the localities visited but few specimens were taken, a 
fact largely owing to their nocturnal habits. They were oftenest 
heard in rocky places, especially among foot-hills. One killed 
near Tombstone, on the evening of April 8, frequently alighted 
on the ground to pick up beetles*. 
123. Chordediles acutipennis texensis ( Lawr .) Ridgw. 
Texan Nighthawk. — Represented in the collection by nine 
specimens from the following localities : Santa Rita Mountains, 
* Naturgeschichte der Voegel, Bd. II, p. 1219. 
f Article, Hermaphroditism, Todd’s Ency. of Anatomy and Physiology. 
