10 NATURAL HISTORY OF KERGUELEN ISLAND 



The measurements are as follows : — 



Nos. 117 a ami b, containing embryos, have been sent to Prof. E. S 

 Morse for examination. 



Larus dominicanus, Vieill. (p. 13.) 

 Nests are built of grass and sea-weed, near the sea, and are gener- 

 ally wet within. Eggs are three in number, and in shape a pointed 

 ovoid, approaching to pyramidal. The shell is rather stout, brittle, and 

 composed of two distinct layers of about equal thickness. The external 

 layer is coarsely granular in texture, roughly mammillated superficially, 

 and of a dark olive-drab color, blotched by irregular spots of different 

 tints, Vandyke-brown, sepia, shite color, and brownish-yellow. The slaty 

 markings are within the shell, the others on the surface. As in the 

 case o( Buphagus, those of the same nest are generally similar in mark- 

 ing, while those of different nests show considerable variety of hue. 

 The internal layer of the shell is closer in texture, of a pale apple-green 

 color, and shows under the lens innumerable small whitish trapezoidal 

 columns set transversely to the surface, in a matrix of a pale-green 

 homogeneous basis-substance. The blotches are more closely aggregated 

 at the large end of the egg than elsewhere, and vary in shade accord- 

 ing to their situation, superficial or deep. Some specimens of these 

 eggs are not distinguishable with certainty from those of northern 

 gulls — Larus argentatus for example. 

 The measurements are as follows: — 



