NATATORES. 425 



an inch long* : all the shafts whitish. Bill and legs vermilion, the former obscurely barred 

 near the tip. 



Form. — Bill rather stout, curved from the nostrils, with the gonys forming an evident 

 salient angle : its depth equal to twice its breadth. Wings an inch and a half longer than 

 the perfectly even tail. Thighs an inch bare. 



A female and another male, killed at the same place six weeks later in the season, cor- 

 respond minutely with the above. 



Dimensions 

 Of the male. 





Inch. 



Lin. 





Inch. 



Lin. 





Inch. Lin 



Length, total 



17 







Length of bill to rictus . 



1 



11 



Length of inner toe . 



. 1 



„ of tail 



. 4 



6 



„ of tarsus 



. 1 



8 



„ of hind toe 



. 3 



„ of wing 



11 







,, of middle toe 



. 1 



3 



„ of hind nail . 



. 2 



„ of bill above . 



. 1 



5 



,, of its nail . 







4i 





— R. 



[190.] 10. Larus Bonapartii. (Nobis.) Bonapartian Gull. 



Genus, Larus, Linn. 

 Akesey-keask. Ce.ee Indians. 



Plate lxxii. 



Ch. Sp. Larus Bonapartii, rostro gracili nigro intus pedibusque puniceis, palliolo perlaceo-cinereo, alis antice 

 late albo marginatis, remigibus sex nigro terminatis apiculis albis ; remige primo extus tolo nigro, tarso 

 sub sesquiunciali. — eucullo cestate nigro. 



Sp. Ch. Bonapartian gull, with a black bill; the mouth and feet carmine-red; wings bordered with white 

 anteriorly : posteriorly, together with the back, pearl-grey ; six exterior quills black at the end, slightly 

 tipped with white : the first quill entirely black exteriorly ; tarsus scarcely an inch and a half long. — Head 

 greyish-black in summer. 



This handsome small gull is common in all parts of the fur countries, where 

 it associates with the Terns, and is distinguished by its peculiar shrill and plain- 

 tive cry. The L. capistratus of the Prince of Musignano (Syn., No. 293) diners, 

 according to his description, in the first quill being white exteriorly, pale-ash 

 interiorly, in the light-brown colour of its hood, and in its tail being slightly 

 emarginated, while the tail of L. Bonapartii is even more inclined to be rounded 

 laterally than notched in the middle. 



DESCRIPTION 



Of a male, killed at Great Slave Lake, May 26, 1826. 



Colour. — Neck, tail coverts, tail, whole under plumage and interior of the wings pure 

 white. Hood greyish-black, extending half an inch over the nape, and as much lower on 

 the throat. Mantle pearl-grey, this colour extending to the tips of the tertiaries, secondaries, 

 and two posterior primaries. The anterior border of the wing is white from its shoulder 



* The extent of black on the second quill is greatest, measuring two inches ; it diminishes gradually on the three 

 succeeding ones, and all these have small white tips. — R. 



3 I 



