OF THE GALAPAGOS ARCHIPELAGO. 479 



6 juv. fusco-niger, dorsi, gulee et pectoris plumis pallide fusco marginatis, abdomine 

 fere fusco unicolori: long. tot. cir. 5'7, alse 3'3, caudffi 2'0, tarsi I'O, rostri a rictu 1'85. 



? fusca, corporis plumis omnibus pallide fusco late marginatis : abdomine fere fusco 

 unicolori: long, tota cir. 5'7, alse 3'35, caudse 2'0, tarsi I'O, rostri a rictu 0'9. 



Hai. Charles Island and Chatham Island {Darwin). 



Mus. Brit. 



This species, the largest of the genus, did not come under Dr. Habel's notice. The 

 only specimens I have seen are Mr. Darwin's types, now in the British Museum. 



I have little doubt that a large series of the skins of this bird would show that the 

 dimensions of the species graduate into those of G. strenua. 



The accompanying woodcut shows the outline of the bill of G. magnirostris. 



Geospiza magnirostris, 



Geospiza STBENUA. 



Geospiza strenua, Gould, P. Z. S. 1837, p. 5 ; Darwin, Zool. Voy. Beagle, iii. p. 100, t. xxxvii. ; 

 Scl. & Salv. P. Z. S. 1870, p. 323; Suiidev. P. Z. S. 1871, p. 124. 



6 (Bindloe Island) niger unicolor, crisso albo marginato : rostro nigerrimo : long, 

 tota 5-75, alffi 3*2, caudce 2-0, tarsi I'O, rostri a rictu 0'75. 



6 junior (Bindloe Island) fuliginoso-niger, dorsi et abdominis plumis fusco margi- 

 natis: rostro nigricanti-comeo, flavido variegato: long, tota 5'75, alse 3'2, caudse 1'9, 

 tarsi 0"95, rostro a rictu 0'75. 



6 hornot. (Bindloe Island), ? omnino similis, dorso et pectore forsan paulo obscurio- 

 ribus: long, tota 6'0, alee 3'1, caudse 1'8, tarsi I'O, rostri a rictu 0'75. 



S (Bindloe Island) fusca, corporis plumis undique pallide fusco late marginatis: 

 abdomine fere fusco-albido unicolori: long, tota 5-5, alae 2-9, caudse 1'9, tarsi 0-95, 

 rostri a rictu 0'8. 



Hab. James Island and Chatham Island {Darwin) ; Indefatigable Island, Bindloe 

 Island, and Abingdon Island {Habel); James Island {Sundevall). 



The greatest variation prevails in the coloration of the males of this species. The 

 absolutely black birds, which are doubtless the oldest males, are very few in proportion 

 to the mottled ones, numbering only nine out of sixty-three specimens (male and 

 female) before me. Of these nine three have yellowish marks on their bills. Between 

 the wholly black birds and the youngest males there is every gradation of plumage, 

 until we come to birds that do not differ appreciably from the females. 



As regards the variation in size, especially of the bill, I find that no set of dimen- 

 voL. IX. — PAET IX. May, 1876. 3 t 



