2O2 



PATAGONIAN EXPEDITIONS: ZOOLOGY. 





to the inner web. Third primary similar, but with more subterminal 

 black. Fourth primary similar, but with the greyish black inner web 

 joining the shaft. Fifth primary greyish black on both webs and with a 

 subterminal bar which is frequently incomplete. The other primaries 

 grayish black. Under wing coverts grey. 



Tail: White. 



FIG. 121. 



Larus maculipennis. Wing, ^ natural size. Adult. From material in the Princeton Museum. 



Lower parts : White, with a blush of roseate tinge on the breast and 

 the abdomen. This blush is evanescent and is very likely to fade in the 

 skins, so as to disappear, even when kept from the light. 



Bill: "Crimson" (Gibson). Tarsi: "Dull red" (Gibson). Toes: 

 "Dull red" (Gibson). Iris: "Dark brown" (Gibson). 



The adult breeding plumage of the female is not to be distinguished 

 from that of the adult male. 



FIG. 122. 



Larus maculipennis. Profile of head. From material in the American Museum. Natural 

 size. Immature. 



