PETROCHELIDON SWAINSONI 

 ERYTHROGASTRA. 



Hirundo erythrogaster X swainsoni, Salvia, Ibis, 1888, p. 25G. 



The figure of the hybrid Swallow is taken from the Cozuniel specimen in the Salvin- 

 Godrnan collection. Mr. Salvin lias given the folloAving account of it : — 



" A single specimen, shot in May 1-885 by Mr. Gaumer on Cozumel Island, we have 

 little doubt is a hybrid between Hirundo erythrogaster and Petrochelidon sicainsoni, as it 

 curiously combines the characters of both birds. The forehead is the same in both 

 species, but the ear-coverts and the collar are steel-blue, as in II. erythrogaster ; the tail 

 is also furcate, though to a less extent, and the lateral feathers have the characteristic 

 white spots ; the wings, too, are as long as those of H. erythrogaster, and the under 

 tail-coverts are tinged with rufous. The characters it has with P. swainsoni are the 

 colouring of the under surface, including the black gular patch ; it also has the rump 

 rufous grey. Instances of hybrids between if. erythrogaster and P. pyrrhonota have been 

 recorded, but this is the first we have met with in which P. swainsoni appears to have 

 been one of the parents." 



It will be seen that the colour of the plumage partakes of the characteristics of both 

 species, the general features of the Petrochelidon being preserved, while the slightly forked 

 tail, and, above all, the white spots on the latter, are the characters of a true Hirundo. 

 We have considered that the strain of the Petrochelidon is stronger in this curious hvbrid 

 than that of the Hirundo, and have named it accordingly. 



That the American Swallow {Hirundo erythrogastra) does occasionally cross with 

 the Cliff-Swallow {Petrochelidon pyrrhonota) is also known, and a full description of a 

 hybrid between these two species is given by Mr. Spencer Trotter in the ' Bulletin of 

 the Nuttall Ornithological Club ' for 1878. This specimen was procured at Linwood, 

 Delaware County, in Pennsylvania, on the 22nd of May, 1878, by Mr. C. D. Wood. 



