MUSCICAPIN^. MILVULUS. 
37 
51. 7. Hirundo serripennis, Aud. Rough-winged Swallow. 
Tail slightly emarginate, margin of first quill rough with the strong 
decurved tips of the filaments^ tarsus bare ; upper parts greyish-brown, 
lower pale greyish-brown, white behind. Very nearly allied to the 
last in form and colour, but readily distinguishable by drawing the 
finger along the edge of the wing, when the stiff projecting tips of the 
filaments are felt like the edge of a fine saw. 
MaUs 5 1, 12 J. 
Louisiana and South Carolina. Migratory. 
Rough-winged Swallow, Hirundo serripennis, Aud. Orn. Biog. v. iv. p. 59 S. 
FAMILY VII. MUSCICAPIN^. FLYCATCHERS. 
Bill depressed, triangular, compressed at the end, upper 
mandible notched, lower with the point slightly ascending. 
Head rather large, depressed ; neck short ; body rather 
slender. Feet generally short ; tarsus short, slender, with 
very broad scutella ; toes four, free ; the hind toe not pro- 
portionally large ; claws arched, compressed, acute. Plu- 
mage soft and blended Wings long, with the first quill 
generally long, the outer three longest. Tail various. 
Tongue flattened, sagittate, bristly at the tip ; oesophagus 
wide, without crop ; stomach elliptical, moderately mus- 
cular, with the lateral muscles distinct, the epithelium 
thin, dense, longitudinally rugous ; intestine short ; coeca 
extremely small ; cloaca globular. Trachea simple ; infe- 
rior laryngeal muscles, forming on each side a large pad, 
but not divisible into several portions as in the singing 
birds. Nests regularly formed, cup-shaped. Eggs from 
four to six. 
GENUS I. MILVULUS, Swains. SWALLOW-TAIL. 
Bill moderate, rather stout, straight, broad at the base, 
gradually compressed toward the end ; upper mandible with 
the dorsal outline a little convex, the edges sharp and nearly 
perpendicular, with a very small notch close to the small 
deflected tip ; lower mandible with the ridge very broad at 
