PROCELLARIA. 497 
Three genera of this subfamily. are included within our limits—Procellaria, Halo- 
cyptena, and Oceanodroma. They are inhabitants of the Atlantic and Pacific Oceans, 
chiefly north of the Equator, with the exception of Halocyptena, which is confined to 
the Eastern Pacific, from the Galapagos Islands to the coast of Central America. 
PROCELLARIA. 
Procellaria, Linn. Syst. Nat. i. p. 212 (1766); Coues, Proc. Acad. Philad. 1864, p. 79; Salvin, 
Cat. Birds Brit. Mus. xxv. p. 843 (1896). 
The type of the genus Procellaria is the well-known “ Storm-Petrel,” or ‘ Mother 
Carey’s Chicken,” which is widely distributed throughout the Atlantic Ocean, breeding 
north of the Equator. It is distinguished from Oceanodroma, of which Leach’s Petrel 
(0. leucorrhoa) is the type, by its longer tarsus, which exceeds the length of the middle 
toe and claw, while the tail has no distinct fork. 
Only two species are recognized, the common P. pelagica and P. tethys, with the 
latter of which we are alone concerned. 
1. Procellaria tethys. 
Thalassidroma tethys, Bp. J. f. Orn. 1858, p. 47°. 
Procellaria tethys, Towns. Proc. U. S. Nat. Mus. xiii. p. 1427; Salv. Cat. Birds Brit Mus. xxv. 
p. 346°; Rothsch. & Hart. Nov. Zool. vi. p. 199 *; ix. p. 416°. 
Fuliginoso-brunnea, vix schistaceo adumbrata ; uropygio et supracaudalibus pure albis; alis caudaque nigris, 
tectricibus majoribus omnibus et secundariis nonnullis intimis extus clarius brunneis, plagam alarem 
formantibus ; subtus fuliginoso-brunnea, subalaribus medianis et majoribus vix pallidioribus, chocolatinis ; 
subcaudalibus lateralibus extus albis: rostro et pedibus nigris; iride saturate brunnea. Long. tota 
circa 6:0, ale 5:3, caude 2°25, culm. 0°5, tarsi 0°85. (Deser. maris adulti ex Culpepper I. Mus. Brit.) 
2 ad. mari similis. Long. tota circa 5:8, ale 5-2. (Deser. femine adults ex Wenman I. Mus. Brit.) 
Hab. West Coast of CentraL AMERICA ?,—GALAPAGOS Ts.1 45, 
This small Petrel probably occurs on the west coast of Central America, as stated 
by Salvin 3, though we do not know what evidence he had for this statement. 
Messrs. Rothschild and Hartert say that P. tethys was found during the Webster- 
Harris expedition to the Galapagos Archipelago in the seas round the islands of 
Wenman, Culpepper, Albemarle, and Tower4; and more recently Mr. Beck has 
procured specimens in the neighbourhood of Bindloe, North Albemarle, and at sea 
in 1° N. lat., 39° W. long.® It was far more abundant in the northern part of the 
archipelago than in the south, and was generally met with far out at sea*. Mr. C. H. 
Townsend found examples of this Petrel in lat. 40° 22! N., long. 82° 32! W., and 
about 400 to 600 miles east of the Galapagos’. 
The species will doubtless be found to breed on some of the last-named islands. 
54* 
