292 AYES: TASSERES. — XLVI. 



the world. All are strong on the wing, insectivorous, and in our 

 latitude migratory. (Lat., hirundo, swallow.) 



a. Nostrils opening directly upward, with very little membrane bordering 

 inner edge. 

 b. Tail forked for a distance more than half tarsus; bill very stout, curved, 



(plumage lustrous, cf all black) Pkogne, 498. 



bb. Tail even. 



c. Outer web of outer primary without recurved hooks ; (plumage lustrous). 



Petrochelidon, 499. 

 cc. Outer web of outer primary with stiff recurved hooks, obscure in $ ; 



(plumage plain brown.) Stelgidoptehyx, 503. 



aa. Nostril opening laterally, and bordered above by a broad membrane or 

 overhanging scale. 

 d. Tail forked for more than half its length, the outer feathers very 



narrow toward tip; no tarsal tuft Chelidon, 500. 



dd. Tail forked for less than half its length. 

 e. Tarsus without tuft of feathers on its lower part; (plumage lus- 

 trous) Tachycineta, 501. 



ee. Tarsus with a small tuft of feathers on its lower part; (plumage 

 plain brownish). . . Clivicola, 502. 



498. PROGNE Boie. (TLpoKvr). a character in mythology, turned 



into a swallow.) 



941. P. subis (L.). Purple Martix. Lustrous blue-black 

 throughout ; 9 duller, whitish and streaky below. L. 7i. W. 6. 

 T. 3^. N. Am., abundant. (Lat., old name of some bird.) 



499. PETROCHELIDON Cabanis. (nirpa, rock; X eAiSd»;.) 



942. P. lunifrons (Say). Cliff Swallow. Lustrous steel 

 blue; forehead, sides of head, throat, rump, etc., of various shades 

 of chestnut; a blue spot on breast; belly whitish. L. 5i. W. 4j. 

 T. 2 1 . X. Am., abundant, formerly nesting in cliffs, but now 

 building under the eaves of barns. (Lat., luna, moon; frons, 

 forehead.) 



500. CHELIDON Forster. (xeAiS&>i>, swallow). 



943. C. erythrogaster (Roddacrt). Barx Swallow. Lus- 

 trous steel-blue, buffy below; forehead and throat deep chestnut; 

 an imperfect steel-blue collar; tail feathers with white spots. L. 7. 

 W. 5. T. 4±. X. Am., very abundant ; breeding in colonies about 

 barns, etc. (Gr., red-belly.) 



501. TACHYCINETA Cabanis. (raxvKivr]Tos, moving swiftly.) 



a. Ear coverts steel-blue; upper parts with metallic lustre. (Iridoprocne 

 Coues.) 



944. T. bicolor (Vieillot). "White-bellied Swallow. Lufr- 

 trous blue-green, pure white below ; 9 duller. L. 6^. W. 5. T. 2|. 

 X. Am., abundant about water; very handsome. 



