NATURAL SCIENCES OF PHILADELPHIA. 307 



vane wholly of a lighter shade of the same color to within three inches ; this 

 gray ends very abruptly, being almost truncated, as it were ; third, like the 

 second, but the gray extends further (nearly as far on the outer as on the 

 inner web), to within about two inches of the tip, which has a minute gray 

 apical spot ; fourth, wholly leaden gray to within one and a half inches of 

 the tip, which has a larger apical spot than the second ; fifth, the leaden gray 

 body of the feathers is separated from the well-defined and now white apex 

 by a band of black, less than an inch long ; and the gray begins to be edged 

 internally with white ; sixth, gray, fading into white at the tip and internal 

 border, with a small subapical spot of black on one or both webs ; other pri- 

 maries like the sixth, without any black. This "gray" of the primaries is 

 precisely the color of the mantle. Legs and feet in the dried specimen light 

 straw yellow ; probably tinged with coral red in life. Claws black. Dimen- 

 sions : Bill along culmen 1-19 inches ; depth at base -50; width "42; depth 

 at angle same ; nostril to tip - 60. Wing 13-00 ; tarsus 1*25 ; middle toe and 

 claw 1-95. (No. 24,296, S. I. Coll. from Kamtschatka.) 



Habitat. Kamtschatka. 



This is a very strongly-marked species, and one which it is impossible to 

 confound with any other. The fine specimens before me agree in the minutest 

 particulars with Gould's description. Its peculiar characters of the shape of 

 the bill, its color and that of the feet, with the dark mantle and the peculiar 

 style of the markings of the primaries, separate it widely from any other Gull 

 with which I am acquainted. Having never seen the young bird, I am totally 

 unacquainted with the changes of plumage which the species undergoes. 



Having thus characterized the two species of Rissa from the Northwest 

 coast, I proceed to the difficult task of discussing their intricate synonyms. 

 While it is believed that the characters of the species are accurately given, 

 the hope is scarcely indulged that the synonyms are more correctly assigned 

 than they have hitherto been by previous authors. 



Concerning the proper location of no name has there been a greater dif- 

 ference of opinion among authors than of Larue niveus of Pallas ? Many writers 

 consider it a Ilissa, and refer it to the R. hrachyrhync/n of Gould. Bonaparte 

 considers it a true Larus, and makes it a distinct species. I am decidedly of 

 opinion that it is a true Lams, and very closely allied to, if, indeed, not identical 

 with, the Larus brachyrhytickus, Richardson, of this paper. Let us examine the 

 characters given by Pallas. " Rostrum virescente-flavum." There is no trace 

 of greenish in the bill of Rissa brachyrhyncha , which is a clear straw yellow. 

 " Pedes fusci." The feet of Rissa brachyrhyncha are yellow, with a tinge of 

 coral red. With his known accuracy of description, I'allas could hardly have 

 made such a mistake as this ; and hence, I do not see why Bruch has identi- 

 fied the bird with Rissa brachyrhyncha. In Pallas' description thus far, there 

 is nothing absolutely inconsistent with the characters of C. Kotzebui of this pa- 

 per. The description continues, however, "apice alaeruinuigro prseeedenti simil- 

 limus." The preceding species is L. cachinnans, Pall., the description of the 

 primaries of which is, " remiges 1 ad t> extremitate nigrse, extimse sensim nlte- 

 rius ; dua? extimse macula transversa albaet apice, 3 ad (5 tantum apice albse." 

 This is the usual pattern of coloration of the primaries of Herring-Gulls, and 

 very different from that which obtains throughout the genus Rissa, being 

 equally inapplicable to either species of the genus. It is true that the plate 

 gives no indication of these subapical spots on the primaries; but in the case 

 of conflict, the text should certainly have precedence. Is the bird, then, a 

 Rissa ? If we examine Pallas' descriptions of his Larus rissa, L. toi-quatus, or 

 L. gavia, we find that he is very careful to use the expressions " tridactylus" 

 and " subtridactylus," and it seems hardly probable that the rudimental cha- 

 racter of the hind toe would have passed unnoticed. The plate shows the 

 hind toe and claw as fully formed as many species of Larus, and there is no 

 expression in the text contradicting it. While I am thus of opinion that the 



18(3'2.] 



