SULA. 145 



edges of mandibles serrated, that of the upper mandible deeply cleft at the junction of 

 the raaxilla with the quadrato-jugal bar; chin and upper part of throat more or less 

 naked. Wings very long and pointed, the first primary longest. Tail long and wedge- 

 shaped, composed of from twelve to eighteen feathers. Tarsus short ; outer and middle 

 toes subequal ; claws curved, that of middle toe broad and pectinate." 



Ten species of Gannets are known, and in every case considerable time elapses before 

 the full plumage is attained : the European S. bassana is said to require six years. 

 This observation was, however, taken from birds in confinement, and it is more 

 probable that the white plumage is fully assumed by the end of the third year. 



1. Sula bassana. 



Pelecanus bassanus, Linn. Syst. Nat. i. p. 217 \ 



Sula bassana, A. O. U. Check-1. N. Amer. Birds, p. 41 ^; Ridgway, Man. N. Amer. Birds, 2nd ed. 

 p. 76 ' ; Ogilvie Grant, Cat. Birds Brit. Mus. xxvi. p. 425 \ 



Alba, pileo colloque stramineo-fulvo tinctis ; teetricibus alarum albis ; ala spuria et primariis brunnescenti- 

 nigris, secundariis tamen albis ; cauda alba ; rectricibus duodecim, nigris ; gula nuda nigra : rostro pallide 

 cyauesoenti-griseo, basin versus viridescente ; regions nuda oculari et rostri lineis nigris ; pedibus 

 brunnescenti-nigris, seutis pallide viridescenti-cyaneis vel Itete smaragdinis, unguibus albicantibus ; iride 

 flavescenti-alba. Long, tota circa 34-0, alae 19'0, caudse 7'5, culm. 3-75, tarsi 2-25. (Descr. ad. ex 

 St. Kilda. Mus. Brit.) 



2 ad. mari similis. 



Juv. Fumoso-brunnea, plumis maculis albis triangularibus terminates, pileo colloque undique albo minute 

 lineolatim maculatis ; abdomine et pectore albo marmoratis, plumis plus minusve celatim albis, brunneo 

 terminatis. (Descr. exempl. ex Anglia meridionali. Mus. Brit.) 



Ilab. North America, Atlantic coast, from the islands of the Gulf of St. Lawrence to 

 the Gulf of Mexico 2. — Coasts of Western Europe, N. Africa, Madeira, and 

 Canary Is. 



The European Gannet is said to wander in winter to the coasts of the Gulf of Mexico, 

 and we therefore include it in our list. The species breeds in various places on the 

 coasts of Canada and the United States. 



2. Sula cyanops. 



Dijsporus cyanops, Sundev. Priys. Tidskr. Lund, i. p. 218, t. 5 (1837)'. 



Sula cyanops, Grayson, Proc. Bost. Soc. N. H. xiv. p. 302 ' ; Lawr. Mem. Bost. Soc. N. H. ii. p. 316 ' ; 



A. O. U.*Clieck-l. N. Ainer. Birds, p. 40''; fiidgw. Man, N. Amer. Birds, 2nd ed. p. 75"; 



Ogilvie Grant, Cat. Birds Brit. Mus. xxvi. p. 430 ' ; Anthony, Auk, xv. pp. 314 % 316 ",317". 



Alba, alls brunneis ; teetricibus alarum medianis et niajoribus saturate brunneis, primariis nigricanti-brunneis ; 

 Cauda saturate brunnea ; gula summa et facie lateral! antioa nudis, linea plumosa gulari fere quadrata : rostro 

 corneo viridescentl-griseo vel viridescenti-flavo ; regione nuda gulari et oculari schistaceis vel cyanescenti- 

 ni^is ; pedibus schistaceis ; iride flava*. Long, tota circa 35-0, alse 18-0, caudse 7-0, culm. 4-35, tarsi 2-5. 

 (Descr. exempl. ad. ex Ins. Norfolk. Mus. Brit.) 



* Mr. Ogilvie Grant rightly points out that in the varying colours recorded for this species due allowance 

 is not always made for the age of the birds, and it is evident that the soft parts vary considerably according to 

 whether the individual is young or old (c/. Cat. Birds, xxvi. p. 431). 



BIOL. CENTR.-AMEK., Aves, Vol. III., May 1901. 19 



