Order ANSERES.] [Fam. PROCELLARIIDjE. 



PEION BANKSII. 



(BANKS'S DOVE PETREL.) 



" Prion banksii, Gould, Ann. N. H. xiii. p. 366 (1844). 

 Prion rossii, Gray, Cat. Brit. Mus. Anseres, p. 165 (1844). 

 Pachyptila banksi, Smith, 111. Zool. S. Afr. Birds, pi. lv. (1849). 

 Procellaria banksii, Schl. Mus. Pays-Bas, Proc. p. 17 (1863). 

 Pseudoprion banksii, Coues, Proc. Phil. Acad. 1866, p. 166. 



Ad. similis P. turturi, sed rostro latiore, pileo saturatiore et cauda nigro latius terminate distinguendus. 



Adult. Plumage similar to that of P. turtur, but with the crown of the head darker, and a broader terminal 

 band of black on the tail: distinguished by its broader bill. Total length 11*5 inches; wing, from 

 flexure, 9 ; tail 3'5 ; bill, along the ridge l - 35, greatest width at the base - 6, from gape to extremity 

 of lower mandible l - 35 ; tarsus l - 4 ; middle toe and claw l - 5. 



The propriety of retaining the above specific distinction appears to me very doubtful ; but I am 

 unwilling to dismiss the supposed species till the subject has been further investigated. 



Mr. Gould, in treating of the group, says that Prion ariel is much smaller than P. turtur, 

 and that the pectination of the bill is not discernible when that organ is closed, that P. turtur 

 is the most delicate in colour as well as the most slender and elegant in form of the four species 

 inhabiting the southern ocean, that P. banksii has the bill of a breadth intermediate between 

 that of P. turtur and that of P. vittatus and exhibiting the pectination of the mandibles when 

 closed, and that " there is another and broader-billed species than P. vittatus " not yet described. 



Captain Hutton, writing on the same subject, observes : — " A regular sequence of the Prions 

 can be formed from P. vittatus to P. ariel ; and therefore I do not think it desirable to retain 

 more than three specific names, to mark each end and the centre of the chain ; and ariel, as 

 the latest, will have to be omitted. On the New-Zealand coast the intermediate (P. banksii) is 

 much the most common " *. 



In the last observation I cannot concur ; for P. turtur is certainly far more plentiful on every 

 part of the coast that I have visited ; and, as already mentioned in treating of the species, 

 numbers are cast ashore after every gale of wind. According to my experience the broad-billed 

 form is comparatively rare ; and the local museums possess very few specimens. 



* Cat. Birds of New Zealand, 1871, p. 80. 



