PROCELL ARIA CCERULEA, Grmel. 
Blue Petrel. 
Procellaria ccerulea, Gmel. Edit, of Linn. Syst, Nat., tom. i. p. 560.— Lath. Ind. Orn., vol. ii. p. 827. — Gould in 
Ann. and Mag. of Nat. Hist., vol. xiii. p. 364. — List of Birds in Brit. Mus. Coll., part iii. p. 165. 
Blue Petrel, Lath. Gen. Syn., vol. vi. p. 415.— Forst. Voy., vol. i. p. 91. — Lath. Gen. Hist., vol. x. p. 196. 
Another Blue Petrel, Cook’s Voy., vol. i. p. 32. 
Procellaria similis, Forst. Draw., No. 86. 
Forsteri, Smith, Zool. of S. Africa, Birds, pi. 54. — Licht. Edit, of Forst. MSS., p. 59. 
This bird maybe distinguished from every other of the smaller Petrels by the conspicuous white tips of the 
centre tail-feathers. It is a very powerful flier, and I observed it in every part of the ocean I traversed between 
the 40th and 55th degrees of south latitude, both in the Atlantic and Pacific. 
As much confusion exists respecting this species, I may state that it is the Procellaria similis of Forster’s 
Drawings, No. 86, and of Lichtenstein’s Edition of Forster’s MSS. p. 59 ; the Procellaria ccerulea of Gmelin, 
Latham and Kuhl ; and the P. Forsteri of Smith, but not of Latham. 
This, the least of the true Petrels, is generally seen in company with the fairy-like Prion Turtur, from 
which when on the wing it can scarcely be distinguished, unless it passes sufficiently near for the observer 
to note the more square form, and the white tips of the tail, which as well as the silvery ends of the 
secondaries and scapularies show very conspicuously. On my voyage to Australia I first observed it in 
lat. 39° 23' S., long. 54° E. ; as we proceeded it gradually increased in numbers, and was very plentiful 
off the coast of Van Diemen’s Land ; I also met with it in my voyages from Hobart Town to South Au- 
stralia and Sydney; and on my return to England in the beginning of May 1840, I observed it to be very 
abundant off the north-east coast of New Zealand ; tolerably numerous on the 20th of May near Cape Horn, 
lat. 50° S., long. 90° W. ; plentiful midway between Tristan d’Acunha and the coast of America ; and in 
the Atlantic Ocean on the 12th of June, lat. 41° S., long. 34i° W., a few were still hovering round the 
ship. 
The sexes are precisely alike, and may be thus described : — 
Forehead, lores, cheeks, throat, centre of the chest, and all the under surface white ; narrow space be- 
neath the eye, shoulders, and the outer webs of the first primaries deep brownish black ; back of the neck, 
sides of the chest, back, rump, wings and tail grey; the secondaries, scapularies and six middle tail-feathers 
tipped with white ; the two outer tail-feathers almost wholly white, and the shafts of all black ; bill dull 
blackish brown, with a stripe of blue-grey along the lower part of the under mandible ; tarsi and toes delicate 
blue ; interdigital membrane flesh-white traversed by red veins. 
The figures represent the two sexes of the natural size. 
