THE (4 EN US LAllUS. 
253 
rinchus and marinus^ which are also among the largest, — > 
and endmg with those in which the bill is most attenuated, 
such as L. jninutus and roseus, which are the smallest spe- 
cies of the genus. 
1. Larus bathyrinchus, Great-billed Gull. 
L. rostro yjone apicem utrinque gibbo, rubro, dorso alis- 
que ardoisiaceis ^, remigibus caudaeque sub apice fas- 
cia nigris. 
Adult. — Beak shortish very deep, much compressed, 
gibbous in the lateral view both above and below beyond 
the middle, ochre-yellovv to the fore part of the nostrils, 
bright-red at the end : length 2| inches, depth at the knob 
1 inch. " I rides and corner of the mouth bright scarlet. 
Feet greenish-yellow^," claws blackish-brown ; tarsus 2| 
inches long, middle-toe * 2| inches. Wings reaching to a 
little bej^ond the tip of the tail. Total length 24| inches, 
extent 52 inches. Back and wings slate-purple ; primaries 
brownish-black, from the seventh primary to the last se- 
condary quill the tips white, forming a terminal bar, which 
is broadest in the middle; the rest of the plumage snow- 
white, with the exception of a band of brownish-black 
across the tail near the end, including the whole of the 
feathers, excepting the outer, which have only the shaft 
slightly marked. Variations dependent upon age, incuba- 
tion, manners, uses, &c. unknown. 
1 Brown, with a little ash-grey and red, upon a blackish basis. 
2 Not quite so long as the head. 
3 Parkinson. 
4 Including the nail. 
