SANDWICH TEKX. 631 



This species, smaller and less robust than the Caspian 

 Tern, is considerably larger and stouter than the Roseate and 

 Common Terns, from which it is at once distinguishable by 

 its black, yellow-tipped bill. Although not of frequent occur- 

 rence on any part of our coasts, I have been able to procure 

 recent and entire specimens for description. 



Male in Winter. — The general form is slender ; the 

 body rather long, somewhat compressed, but with the pecto- 

 ral muscles well developed ; the neck of moderate length ; 

 the head rather large, considerably compressed. The bill is 

 rather longer than the head, almost straight, being very 

 slightly arched, much compressed, and acuminate. The 

 upper mandible has the dorsal line slightly declinato-arcuate, 

 the ridge convex, narrowed beyond the nostrils, the sides 

 convex, nearly erect toward the end, the edges sharp, direct, 

 overlapping, the nasal groove of moderate length, narrow, 

 with a shallow groove passing obliquely from the nostrils to 

 the margin. The lower mandible has the angle long and 

 very narrow, the commissure somewhat prominent, the dorsal 

 line stright, the sides erect, a little convex, the edges very 

 thin, with an external groove for the reception of the upper, 

 the tip extremely slender and acuminate. The gape-line, 

 which commences below the middle of the eye, is a little 

 arcuate. The mouth is rather wide, measuring nine-and-a- 

 half-twelfths across, and considerably dilatable. The tongue 

 is an inch and seven-twelfths long, very slender, trigonal, 

 emarginate, and papillate at the base, horny, and thin-edged 

 in its terminal two-thirds, channelled above, the tip of two 

 very slender points. 



The nostrils are linear-elliptical, sub-basal, equidistant 

 from the margin and ridge-line, four-tw^elfths long. The 

 eyes are of moderate size, the width of their aperture being 

 four-twelfths. That of the ear very small, measuring two- 

 twelfths. The feet are very small ; the tibia very short and 

 slender, as is the tarsus, which has fifteen anterior scutella. 

 The first toe diminutive, wdth six scutella ; the second consi- 

 derably shorter than the fourth, and with fifteen scutella ; 

 the third with twenty-four, and not much longer than the 



