1845.] or little known species of Birds. 211 



of a Sparrow, or a Robin, but retaining the peculiar configuration ob- 

 servable throughout the passerine type, in all its integrity. It would be 

 out of place here to pass in review the principal details of conforma- 

 tion of the groups to which the Swifts and Swallows respectively belong, 

 and to shew how essentially they differ in the whole skeleton, in the ali- 

 mentary organs, that of voice, &c. ; even to the structure of the feathers, 

 and to the circumstance that the Swifts (like the Trochilidce and Ca- 

 primulgidce,) have never more than ten rectrices, while the Swallows 

 have twelve, in common with the whole of the grand series of passe- 

 rine birds, save one or two peculiar exceptions, of which the Drongo 

 (or King-Crow) group is the most remarkable one. I shall conclude 

 for the present by indicating the Indian species of Cypselidce. 



These fall under four generic heads 



Acanthylis, Boie, v. Chcetura, Stephens : from which Pallene of Les- 

 son, containing the Indian species, is placed separately by Mr. Gray, 

 for reasons with which I am unacquainted. Mr. Hodgson, also, says of 

 the Himalayan species, that it is " certainly not a Chcetura as defined by 

 Stephens. I have set it down in my note book," he adds, "as the type 

 of a new genus, called Hirundapus" (a bad hybrid name, which holds 

 priority over Pallene), Mr. Swainson, however, had long previously fi- 

 gured the same bird as a true Chcetura, from which genus I cannot per- 

 ceive in what it differs. 



1. Ac. gigantea, (Tem.) Inhabits the Malay countries, extending 

 northward to Arracan, where it is of rare occurrence ; it also occurs in 

 the Neilgherries. Chin albescent, but not forming with the throat a large 

 pure white patch, as in the next species ; and the spinous tail-feathers 

 are much stouter, with their webs tapering, and not terminating ab- 

 ruptly as in the other. 



2. Ac. caudacuta* (Lath. J: Hirundofusca, Shaw; Chcetura australis, 

 Stephens ; Ch. macroptera, Swainson ; Ch. nudipes, Hodgson, J. A. S. 

 v. 779; Cypselus leuconotus, Mag. de Zool. 1840, Ois., pi. XX, and 

 figured in the Souvenirs, &c. of M. Adolphe Delessert, pt. II, pi. IX, 



* The Himalayan bird is certainly the macroptera of Swainson; and as this is 

 given as a synonym of Latham's caudacuta by Mr. Strickland, (An. and Mag. N. H. 

 1843, p. 337,) on the authority of the drawing upon which Latham founded his 

 description, now in the possession of the Earl of Derby, I of course bow to the decision 

 of that naturalist; though Latham's statement that it has the "forehead white, and 

 throat very pale dusky," certainly applies better to Ac. gigantea of the Malay countries. 



2h 



