248 Birds of Colorado 
An example of this species was recently secured by Aiken at Hoehne, 
near Trinidad, on June 11th, 1908. This constitutes a new record for 
Colorado. 
Family CYPSELIDZ. 
This family contains the Swifts—birds distinguished 
for their great power of rapid flight. The following 
are a few of the most obvious external characters, 
sufficient to distinguish them: Bill very small, flattened 
and triangular, but with the gape of the mouth very 
large and extending back to under the eye; no rictal 
bristles ; wing long, thin and pointed, made up chiefly 
of the primaries, which are ten in number ; secondaries 
very short and reduced ; tail-feathers ten, variable in 
shape and arrangement ; legs and feet small and weak, 
adapted only for perching ; toes four, variously arranged 
in different genera. 
The salivary glands of the Swifts are very greatly 
developed, and their secretion, which forms a gluey mass, 
is used more or less in the construction of the nest. 
Key or THE GENERA, 
A. Tarsi feathered, plumage black and white. Aéronautes, p. 249. 
B. Tarsi naked, plumage black, no white. Cypseloides, p. 248. 
Genus CYPSELOIDES. 
Nostrils embedded in the frontal feathers; wing with the outer 
primary the longest; tail forked, the feathers obtusely pointed, but 
the shafts not produced to form needle-like points; tarsi naked, hallux 
normal, turned backwards, slightly elevated above the others; 
plumage black. 
An exclusively American genus with five or six species, one of which 
is found in the western United States. 
Black Swift. Cypseloides niger borealis. 
A.O.U. Checklist no 422—Colorado Records—Drew 81, p. 140; 82, 
p. 182; Morrison 89, p, 145; Bendire 92, p. 175 ; Cooke 97, p. 86. 
