TNSESSORES. Ill 



will be found to comprise ample materials for the formation 

 of more genera than has yet been proposed, as well as 

 numerous species with which we are at present unacquainted ; 

 and I have no doubt that Mr. Blyth's notion of dividing 

 them into sections in accordance with the forms of their nests 

 will be found a very happy suggestion — saucer-builders, retort- 

 builders, bank-burrowers, builders in the holes of trees, &c. 



The species of this form are part of a small section of the 

 Swallows which nidify in the holes of trees, without any nest 

 for the deposition of their delicate eggs. Their bare tarsi at 

 once separate them from the Chelidons, and they also differ 

 from the American Petrochelidons. Of these birds, which 

 appear to be an offshoot from the typical or true Hirundines, 

 my collection contains at least two species, one from Australia, 

 the other from Timor ; I say at least, because it is a question 

 whether the birds from Australia do not constitute two in 

 themselves, — specimens from Tasmania being very much 

 larger than those from the main land. 



Sp. 55. HYLOCHELIDON NIGRICANS. 



Tree Swallow. 



Chelidon arborea, Gould, Birds of Austraha, vol. i. Introd. p. xxix. 



Cecropis pi/rrhonota, Boie, Isis, 1844, p. 175. 



Hirundo {Heise) nigricans et pyirhonota, Less. Compl. Buff., torn. viii. 

 p. 497. 



Dun-rumped Swallow, Lath. Gen. Hist., vol. vii. p. 309. 



Hirundo pyrrhonota, Vig. and Horsf. in Linn. Trans., vol. xv. p. 190. 



Hirundo nigricans, Vieill. Ency. Meth,, part ii. p. 525. 



Cecropis nigricans, Boie, Isis, 1844, p. 175. 



Petrochelidon nigricans, Cab. Mus. Hein. Theil i. p. 47. 



Gab-by -kal-lan-goo-rong. Aborigines of the lowlands of Western Aus- 

 tralia. 



Martin of the Colonists. 



Collocalia arborea, Gould, Birds of Australia, foL, vol. ii. pL 14. 

 The Tree Swallow is a very common summer visitant to 



