94 



BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 



of bill at frontal antias, 5; tarsus, 11-12 (11.5); middle toe, 10-11 

 (10. 5). « 



Adult female. — Similar to the adult male but much duller in color; 

 pileum and hindneck varying from bronzy green to bronzy purple; 

 back and scapulars varying from dull bronzy green to dull bronzy 

 purple (usually the latter), the back becoming green across upper 

 margin; middle line of rump and upper tail-cov^erts dull green; auricu- 

 lar region and supraorbital spot mottled with gray; otherwise like the 

 adult male, but white of under parts less pure, more or less tinged 

 with pale gray anteriorly: length (skins), 113-123 (118.7); wing, 110- 

 116 (113.3); tail, 46-48.5 (47. 2); exposed culmen 5.5-6 (5.7); width of 

 bill at frontal antise, 4-5 (4.3); tarsus, 11-12 (11.7); middle toe, 10-11 

 (10.3)." 



Mexican plateau, north to State of Chihuahua,^ south to States of 

 Vera Cruz (Orizaba, etc.), Mexico (Valley of Mexico), and Oaxaca 

 (Mitla).^ 



Hirundo thalassinus Swainson, Philos. Majj., new ser., i, 1827, 366 (Real del 

 Monte, Hidalgo, Mexico; coll. Bullock Mus. ) ; Isis, 1834, 783. 



Hirundo thalamnu Bonaparte, Geog. and Comp. List, 1838, 9, part. — Baird, 

 Review Am. Birds, 1865, 299, part (Mexico; Orizaba, Vera Cruz). — Baird, 

 Brewer, and Ridgway, Hist. N. Am. Birds, i, 1874, 347, part. 



IIir[undo\ thalasdna Boie, Isis, 1844, 171. 



Hlirundo'] thalassina Gray, Gen. Birds, i, 1845, 58. 



IHirundo'] thalassina Gray, Hand-list, i, 1869, 71, no. 841. — Coues, Key N. Am. 

 Birds, 1872, 113, part.— Sclater and Salvin, Nom. Av. Neotr., 1873, 14, 

 part. 



Cecropis thalassinus Lesson, Compl. Buffon, viii, 1837, 499. 



[Herse] thalassina Bonaparte, Consp. Av., i, 1850, 341, part. 



T[achycineta'] thalassina Cabanis, Mus. Hein., i, 1850, 48 (Mexico). — Baird, 

 Brewer, and Ridgway, Hist. N. Am. Birds, i, 1874, 344, part. — Coues, Key 

 N. Am. Birds, 2d ed., 1884, 323, part.— Ridgway, Man. N. Am. Birds, 1887, 

 462, part. 



« Three specimens. 



^ Two specimens from Chihuahua (exact locality unknown) in the collection of 

 the American Museum of Natural History are similar to typical examples from the 

 Valley of Mexico in coloration, but are smaller. Their measurements are as follows: 



c An adult female from Mitla in the Biological Survey collection (no. 143514, U. S. 

 Nat. Mus. ), collected June 28, agrees with typical T. thalassina in larger size, and green 

 instead of blue or purplish upper tail-coverts, but has the back and scapulars bronzy 

 green, without any purplish tinge. 



