CYPSELID^: SWIFTS. 
455 
and southward, common. General habits and traits of a night-hawk, but the difference between 
the two is obvious when they are flying. Eggs 2, heavily veined and marbled, 1.20X 0.87- 
22. Family CYPSELID^ : Swifts. 
Tig. 296. Northern Black Cloud Swift, nat. size. (E. H. Fitch.) 
Fissirostral Picarice : 
Bill very small, flattened, 
triangular when viewed 
from above, with great 
gape reaching below the 
eyes; unnotched, unbris- 
tled, the gape about six 
times as long as the cul- 
men. Nostrils exposed, 
superior, nearer culmen 
than commissure, the 
frontal feathers tending to 
reach forward under them. 
Wings extremely long, 
thin, and pointed (fre- 
quently as long as the 
whole bird) ; the prima- 
ries acute and somewhat 
falcate ; the secondaries 
extremely short (nine?). 
Tail of 10 rectrices, va- 
riable in shape, often 
mucronate. Feet small, 
weak, the envelope rather 
skinny than scaly; tarsi 
naked or feathered ; hind 
toe frequently elevated, or 
versatile, or permanently 
turned sideways or even 
forward; lateral toes near- 
ly or quite as long as 
the middle; anterior toes 
deeply cleft, the basal 
phalanges extremely short, 
the penultimate very long, 
the number of phalanges 
frequently abnormal (2, 3, 
3, 3, instead of 2, 3, 4, 5 ; 
see p. 127, fig. 40) ; claws 
sharp, curved, never pecti- 
nate. Plumage compact, 
usually sombre and whole - 
colored, or only relieved 
with white; sexes alike. 
Sternum deep - keeled, 
