o 



410 A PRACTICAL HANDBOOK OF BRITISH BIRDS. 



HYDROBATES PELAGICUS * 



332. Hydrobates pelagicus (L.)— THE STORM-PETREL. 



Pro cell aria pelagica Linnaeus, Syst. Nat., ed. x, i, p. 131 (1758 — 



"Habitat in albo j* Oceano." Restricted typical locality: coast of 



Sweden). 



Procellaria pelagica Linnaeus, Yarrell, iv, p. 42 ; Saunders, p. 727. 



Description. — Adult male and female. Winter and summer. — 

 Upper-parts sooty-black, fore-head and fore-part of crown and lores 

 and chin paler, tinged brown or greyish ; lower -rump and upper 

 tail -coverts white, feathers with black or dark grey shafts, those 

 nearest rump with brown bases, and those nearest tail with long 

 sooty-black tips (sometimes restricted to a spot on lateral feathers) ; 

 under-parts sooty-brown, bases of feathers greyish ; under tail- 

 coverts same but bases whiter, usually 

 concealed but sometimes showing on 

 lateral feathers ; feathers of lower - 

 flanks adjoining rump with outer webs 

 white ; axillaries sooty-brown with 

 white tips ; under wing -coverts sooty - 

 brown, those covering primaries with 

 — faint whitish tips and those covering 



™. o- t> 4. i/rr * , , secondaries with longish whitish tips, 



The Storm-Petrel (Hydrobates , & . . , . K 



pelagicus). median ones with whitish tips mostly 



confined to outer webs and forming 

 irregular whitish patch in middle of under-wing ; tail sooty- 

 black, bases of all feathers except middle pair white with 

 black shafts ; wing-feathers with black outer and sooty-brown 

 inner webs, bases of inner webs of secondaries white, innermost 

 secondaries with faint greyish-white tips and edges ; wing-coverts 

 as rest of upper-parts but greater coverts with greyish-white tips 

 and edges to outer webs varying in width but narrow. This plumage 

 is acquired by complete moult, Period varies but ranges from 

 Sept. to May some not completing even until June and July although 

 in others moult is just finishing Nov. J In worn plumage under- 

 parts are browner and white edgings to greater coverts and inner 

 secondaries are much reduced by abrasion. 



Nestling (Plate 7). — 1st down, greyish sooty-brown, slightly 

 paler on under- than upper -parts, soft and long, covering bird very 

 closely except lores, round eyes and chin which are nearly bare. 



* In the Cat. B. Brit. Mus. this species has been called Procellaria 

 pelagica, and it has been stated that P. pelagica was the type of Procellaria. 

 This is an error (cf. Nov. Z00L, 1910, p. 497). American and other authors 

 have accepted the generic name Thalassidroma, but Hydrobates is older, and 

 it need not be rejected on account of the previous name Hydrobata. — E.H. 



t Doubtless misprint for " alto." — E.H- 



J It seems probable that those finishing moult in summer are birds 

 hatched the year before and that adults moult in autumn and winter. — H.F. W. 



