1846.] or Little Known Species of Birds. 3 



B. pygmceus, nobis, J. A. S. 1845, p. 177, is a fifth decided species, 

 from the Tenasserim provinces. 



To the genus Spizaetus of Vieillot, Mr. G. R. Gray refers Nisaetus of 

 Mr. Hodgson as a synonyme (as I formerly did, in J. A. S. XI, 456, 

 and XII, 305) ; thus bringing together certain species of the Old World 

 and of the New, concerning which suspicion at least of respective generic 

 diversity had been entertained. Morpknus of Cuvier, however, which had 

 generally been placed as synonymous with Spizaetus, is confined by Mr. 

 Gray to certain naked-legged species of South America, as M. urubi- 

 tinga and its affines ; and, finally, Limnaetus, Vigors, is referred by the 

 same systematist to Spixa'etus, though to judge from Dr. Horsfield's 

 figure and description of L. unicolor (its type), he would scarcely seem 

 justified in doing so. 



Upon a former occasion {ante, p. 176), I indicated the four Indian 

 species of undoubted Spizaetus (vel Nisaetus), after describing what I 

 conceived to be a new species of the form from Malacca, by the name 

 Nisaetus alboniger* This last, however, proves to be decidedly the 

 true Falco caligatus of Raffles, (as was first pointed out to me by my 

 friend Dr. Cantor,) and will therefore now range as Sp. caligatus, 

 (Raffles) : consequently, it remains to determine what specific name 

 the common Bengal species, which I formerly conceived to be cali- 

 gatus, should retain ; and this will probably be nipalensis, (Hodgson,) 

 since considerable doubt must attach at present to the identification 

 of it with the Javanese Falco niveus of Temminck. The species in 

 question is the Bauj Eagle and Nerwied Eagle of Latham, but does not 

 appear to have received a distinctive systematic name prior to that 

 bestowed by Mr. Hodgson, and which should refer exclusively to his 

 supposed crestless variety of the species, which usually presents a mere 

 rudiment of an occipital crest, very rarely further developed ; though I 

 have obtained one middle-aged specimen (out of several dozens,) with a 

 crest two inches long.f This bird would appear to be very rare in the 

 Himalaya, while in the plains of Lower Bengal it is extemely numer- 

 ous. I lately saw one specimen in a large collection froB^Darjeeling : 

 but Mr. Hodgson's supposed crested variety of the species, wbsequently 



* Also described under this name by Lord Arthur Hay, Madr. Journ. No XXXI, 

 145. 



t More recently, also, another and younger specimen, with a slight crest, though still 

 very unusually developed for the species. 



