100. PRION BREVIROSTRIS, Gould, 



(SHORT-BILLED BLUE PETREL.) 



(Plate 85.) 



Prion ariel, Gould, Ann. and Mag. Nat. Hist., XIIL, p. 366 (1844 : descr. nulla) ; id., 

 Handb. Birds Austr., II., p. 473 (1865) ; Giglioli, Faun. Vertebr. Oceano, 

 p. 45 (1870) ; Buller, Birds New Zeal., 2nd ed., II., p. 213 (1888) ; Salvin, 

 Cat. Birds Brit. Mus., XXV., p. 436 (1896). 



Prion brevirostris, Gould, P. Z. S., 1855, p. 88, PI. 93 ; Buller, Suppl. Birds New 

 Zeal., I., p. 125 (1905) ; Reichenow, Deutsche Siidpolar Exped., IX., Zool., 

 I., p. 557 (1908). 



Procellaria ariel, Gray, Ibis, 1862, p. 247 ; Scbl, Mus. Pays-Bas, VI., Procell., p. 18 

 (1863). 



Pseudoprion ariel, Coues, Pr. Acad. Philad., 1866, pp. 166, 172. 



Pseudoprion brevirostris, Coues, t.c, pp. 167, 172. 



Pachyptila ariel, Cab. and Reichen., J. f. O., 1876, p. 328. 



Ad. P. desolato similis, pulchre cyanescenti-cinereus, pileo dorso concolori, haud 

 fuscescentiore : rostro parviore, breviore, tamen crassiore distinguendus. 



This species is closely allied to P. desolatus, and resembles it in colour ; the chief 

 difference lies in the shorter and stouter bill of P. brevirostris, which varies greatly in 

 size, the sides not being bowed in towards the tip, while the lamellae are evanescent. 



The head and back are alike in colour, and no sign of a darker cap is visible ; the 

 under tail-coverts seem to be more blue-grey and are less white towards the base than 

 in P. desolatus. This appears however to be a variable character, and I do not attach 

 much importance to it, or to the supposed greater extent of black at the end of the 

 tail* 



The following is a summary of the measurements of the series in the British 

 Museum : — 



Oilmen. Width of Oilmen. Wing. Tarsus. Middle Toe and Claw. 



0.88-0.98 0.35-0.4 6.3-7.35 1.1-1.3 1.4-1.55 



Gould's name for this Prion must be changed, as although he quotes his 



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