‘ANOUS. 413 
2. Anous pileatus. 
Le Petit Fouquet des Philippines, Sonn. Voy. Nouv. Guin. p. 125, t. 85°. 
Sterna pileata, Scop. Del. Faun. et Flor. Insubr. ii. p. 92, ex Sonnerat’. 
Anous pileatus, Gray, Gen. Birds, iii. p. 661°. 
Anous stolidus pileatus, Hartert, Nov. Zool. vii. p. 9°. 
Anous rousseaui, Hartl. Beitr. Orn. Madag. p. 86°. 
Anous stolidus rousseaui, Ridgway, Pr. U.S. Nat. Mus. xix. p. 645 °. 
Anous stolidus (nec Linn.), Scl. & Salv. Ibis, 1859, p. 283"; Lawr. Mem. Bost. Soc. N. H. u. 
p. 818°; Baird, Brewer, & Ridgway, Water-Birds N. Amer. ii. p. 325, pt.°; Saunders, Cat. 
Birds Brit. Mus. xxv. p. 137”. 
Anous stolidus ridgwayi, Anthony, Auk, xv. pp. 36, 316"; Nelson, N. Amer. Fauna, no. 14, p. 26”. 
Anous ridgwayi, Sharpe, Hand-l. Birds, i. p. 137 °; Oates, Cat. Eggs Brit. Mus. i. p. 198, t. 15. 
fig. 6". . 
A. stolido similis, sed saturatior, nigricantior, notszo toto, gutture et pectore antico plumbeo lavatis; facie 
laterali nigricanti-plumbea, loris et regione oculari nigerrimis ; palpebris albis; pileo antico canescente, 
fronte basali et linea angusta superciliari albis, pileo postico graduatim cinereo, nucha vix a collo reliquo 
diversa. Long. tota circa 15-0, ale 10-7, caude 6°4, culm. 1°5, tarsi 0°85. (Descr. femine adult ex 
Clipperton I. Mus. Rothschild.) 
Hab. Revittaciceno Is., Socorro I. (Anthony *).—W. Mexico, Isabel Island off San Blas 
(Grayson8, Nelson’), Tres Marias Is. (Nelson 1”), Clipperton I. (Beck); GuATEMALA, 
Pacific coast (O. S.7).—Paciric Oczan generally, from the Philippines and coast of 
China to Laysan + 1°. 
The Pacific Noddy appears to be distinguishable from the true A, stolidus of the 
Atlantic, but its full range has yet to be determined. I see no reason, however, for 
doubting the conclusion arrived at by Mr. Hartert, that the birds examined by him 
from the Caroline Islands are specifically identical with those from the Revillagigedo 
group; a Formosan specimen in the British Museum also seems to be of the same 
species. The Noddy of Madagascar (A. rousseaut) is also considered by Mr. Hartert to 
belong to the Pacific form, the oldest name for which appears to be Sterna pileata, 
Scopoli. It is this form also which Mr. Anthony recently described as Anous ridgwayt 
from Socorro Island, and Mr. Rothschild has kindly lent me several specimens from 
Clipperton Island, Laysan, and the Carolines, all of which seem to belong to one and 
the same species. | 
Mr. Hartert 4 points out that the Pacific form of the Noddy has a longer and more 
graduated tail than the true A. stolidus. The crown is greyer and never inclining to 
white, as in the latter bird, and the general colour of the plumage is more sooty and 
not so brown. On comparing the series of specimens lent by Mr. Rothschild, it 
seems to me that these characters are recognizable, and I have therefore acknowledged 
Anous pileatus as distinct from A. stolidus. 
Grayson met with the Pacific Noddy on Isabel Island, near San Blas®, and 
Mr. Nelson observed it near the Tres Marias Islands *. Mr. Anthony obtained his 
