ORNITHOLOGICAL EXPLORATIONS. 269 



122. Chelidon tytleri (Jerd.). 



1826. — Hirundo doviesiica var. Pall., Zoogr. Ross. Asiat., I, p. 530 (part). 



1853.— Eirundo rustica var. rufa Middend., Sibir. Reise, II, 2 (p. 188) {nee Gmel.). 



1858. — Hirundo rufa Kittlitz, Denkwiird., II, p. 196 (wee Gmel.). 



1862. — Hirundo rustica Radde, Reise Siiden Ost-Sibir. (p. 278) {nee LiN.). 



1864, — Hirundo tytleri Jerdon, Birds of India, III, p. 870. 



1876.— Hirundo amcrica naBLAKiST., Ibis, 1876, p. 331.— Blakist. & Pryer, Trans. As. 



Soc. Japan, VIII, 1880, p. 211 {nee Wilson). 

 1882. — Hirundo erythrogastra Blakist & Pryer, Trans. As. Soc. Japan, X, p. 139 {nee 



Bodd.)— Blakist., Amend. List B. Jap., p. 47 {188A).— Chelidon erythro- 



gasier Stejneger, Pr. U. S. Nat. Mus., VI, 1883, p. 72. 

 1882.— ^(>H/ifZo guituraUs Taczan., Bull. Soc. Zool. France, 1882, p. 385 {nee Scop.)—. 



Dybowski, Bull. Soc. Zool. France, 1883, p. 357. 

 1883.— Hirundo saturata "Stejneger MSS.," RiDCxW., Pr. U. S. Nat. Mns., VI, 1883, 



p. 95. 

 1885. — Hirundo rustica subsp. tytlo'i Sharps, Cat. B. Brit. Mus., X, p. 140. 



A careful comparison with a large series of American specimens of 

 Ch. erythrogastra shows the following differences : 



1. As will be seen from the tables below, the dimensions agree pretty 

 well, except that the lateral rectrices, although subject to great indi- 

 vidual variation, are, on the average, considerably shorter in the Ameri- 

 can species, while the middle ones are of the same length. 



2. The darkest American male is perceptibly paler than even the 

 females of the Kamtschatkau form. In the latter species the color of 

 the chin and throat is as deep as in the most richly colored specimens 

 of the true European ritstica, and the difference between the color of 

 these parts and that of the breast and abdomen is very slight, and 

 much less abrupt than in Ch. erythrogastra., and the trace of the black 

 breast-band is more strongly indicated than in the latter. In tytleri 

 the brown of the forehead reaches considerably higher ui) on the head, 

 and the feathers of the tibia are whitish, strongly contrasted with the 

 rich chestnut-rufous of the abdomen, while in erythrogastra they are 

 hardly paler than those of the surrounding i^arts. 



There seems thus to be little need of confounding these two birds, 

 which may be considered distinct species, as no intergradation is known 

 to occur. Nor is it likely that any will be found. 



As to the Asiatic relatives of the Kamtschatkau species it may be re- 

 niarked that Taczauowski describes two different forms, one darker, 

 from Dauria and the Baical, and the other, a paler form, from Amur, 

 Ussuri, and China. From the descriptions given by v. Schrenck, and es 

 pecially by Taczanowski in J. f. Orn., 1875, p. 244, 1 have little hesitation 

 in referring the latter to a form very closely allied to the Japanese true 



