THE AFFINITIES OF CIIAETURA. 
BY FREDERIC A. LUCAS. 
For a Icing time the Swifts have been debarred from the society 
of passerine biids and made to associate with those- contained in 
that 'avian waste basket, termed the order Pica-rise, Of late, 
however, several ornithologists, notably Mr. Sharpe and Dr. 
Pafkbr, have advanced it pled for their reinstatement : in the order 
Passeres. Latest of these' is Dr. Slnifeldt who reaches the con- 
clusion* that ‘‘the Swifts are essentially modified Swallows, -and* 
as the family Cypselidae, they belong, in the -order Passeres, next 
to that group.”' 
Notwithstanding 1 the evident care of Dr. Shufeldt’s work I must 
confess myself as unconvinced by the evidence he brings forward 
and will briefly review the case of- Chceturd as a plea for the 
continued separation of Swifts and Swallows and the retention of 
the first named family near the Hummingbirds. I am well aware 
of the risk I run-in opposing my own slight knowledge of the 
subject to the results of Dr. Shufeldt’s more extended studies* 
and it is with still greater diffidence that I venture to disagree 
with so distinguished a morphologist as Dr. Parker. Nevertheless, 
until still more evidence to the contrary is adduced, I will hold 
fast to Huxley’s union of Hummingbirds’ and Swifts. As for 
the Caprimulgidae, there are few, I think, who will object to their 
* Contribution to the Comparative Osteology of the Trochilidte, Caprimulgidte, and 
Cypselidte. Proc. Zool. Soc. London, Dec. i 1885. 
1SS6.] 
Lucas on the Affinities of Clicetura. 
445 
being placed in an order by themselves. They are a most 
attractive group of birds for study, and all that I have examined 
or seen figured offer good cranial generic characters, which is 
more than can be said for most birds. In the ensuing compari- 
sons Trochilus maybe construed as T. columns, while Chelidon 
stands for C. erythrogaster , this bird having been chosen 
simply because its name is a little less formidable than that of 
most Swallows, and not from any peculiarity of its skeleton. 
Before taking up the more salient structural characters, it may 
be well to say that, viewed in profile, the skull of Chcztura is 
very suggestive of Chordeiles , while that of Chelidon unmistak- 
ably resembles that of a Flycatcher. The sphenoidal rostrum of 
Chcztura is broad, the palatines are separated from one another, 
and the pterygoids are in close proximity to the basi-temporal 
region,* all characters wherein Chcztura agrees with Trochilus 
and differs from Chelidon. This bird has the rostrum narrow, 
the palatines applied to each other posteriorly, and the pterygoids 
standing well out from the basi-temporal region, as in the higher 
Passerines. In Chcztura the curiously expanded end of the vomer 
abuts on the maxillo-palatines, with which in young birds it is 
intimately connected. While this is wholly unlike the sharp- 
pointed, anteriorly free, vomer of Trochilus , and more nearly re- 
sembles the typically passerine vomer of Chelidon , yet the vomer 
of Chelidon is quite free from the maxillo-palatines, although it 
overlies them for its entire length. Now, among the Goatsuckers, 
Chordeiles has a slender, pointed vomer, which at first rests upon 
and later in life coalesces with the united maxillo-palatines, while 
in Antrostomus, and to a less extent in Nyctidromus , the vomer 
is broad and at its free extremity articulates with the maxillo-pala- 
tines. Assuredly there is an interesting suggestion of relation- 
ship between Chcztura and the Goatsuckers, and a study of the 
embryology of the former bird would undoubtedly yield good re- 
sults. The maxillo-palatines of Antrostomus terminate in recurved 
points which bear a certain resemblance to the slender, curved 
maxillo-palatines of Chcztura. In Chelidon these bones are ex- 
panded at their free extremities, these expansions having the 
^Perhaps I over estimatethe importance of this last character, but it is a pronounced 
feature of many ‘Picarige,’ notably of the Woodpeckers and Goatsuckers, less so of the 
Cuckoos. 
