48 A. von Pelzeln on Birds in 



breviore, alis longioribus, cauda longiore, magis gradata, 

 tarsibus extus, exceptis lineis duabus, flavidis, plantis 

 margine obscuro nullo, plumis colli et pectoris laterum 

 albo marginatis ; 

 a P. nugaci (Soland.), ex Australia, statura majore, colore 

 notaei nigricante brunneo nee scliistaceo nigro, loris 

 brunneis nee albis, tarsibus extus, exceptis lineis duabus, 

 flavis et plantis baud nigro limbatis differt*; 

 a P. dichroo, Hartl. et Finsch, statura majore, hypochon- 

 driis albis et pedibus non nigricantibus aut nigricanti- 

 cinereis diversus. 

 Specimen, Sale Cat. n. 6079 (Petrel, from King George's 

 Sound, N. America). 



This bird, mentioned as different by Latham himself, was 

 separated by Natterer in his MS. Synopsis as belonging to 

 a different species, under the name Puffinus tenebrosus. 



I add a translation of Natterer' s MS. description (dated 

 19th May, 1839). 



" Puffinus tenebrosus (from the Leverian Museum) . 

 " In form and colour strikingly similar to P. obscurus, but 

 smaller, with thinner and shorter bill, somewhat longer wings, 

 and a little longer, more cuneiform tail. The outside of tarsus 

 light-coloured only a little above the articulation of the toes 

 outwardly, and the outer side of the external toe dark brown, 

 the margins of the webs light-coloured, the claws also not so 

 black as those of P. obscurus. 



" On the entire side of the throat, from the ear as far as the 

 side of the upper breast, the dark brown feathers are fur- 

 nished with a broad white margin. P. obscurus has these 

 margins only on the sides of the upper breast. 



Unit. St., Gulf of Mexico) ; Gray, Gen. 647, et App. 29 ; Bonap. Consp. 

 ii. 204; Baird, Eep. 1858, 835; Gray, Birds Tropic. Isl. Pacif. Oc. 55 

 (excl. syn.) ; Hartl. Fauna Madag. 84 (Bourbon, Mauritius, Madagascar). 



Puffinus nugax, var. bailloni, Bonap. Compt. Rend. xli. (1856) 8 ; Tabl. 

 Longip. sp. 80 ; idem, Consp. ii. 205 (He de France). 



Puffinus bailloni, Bp. ; Hartl. Fauna Madag. 84. 



* For comparison with P. obscurus I have referred to a specimen 

 (probably from the American coast) received in exchange from the Paris 

 Museum in 1815, and another (somewhat smaller) from Madagascar, 

 purchased by Natterer. Of P. nugax I have compared a specimen from 

 New Holland, obtained from M. Verremix. 



