CAYENNE TERN. TjOO 



the sides slightly convex, nearly erect, the sharp edges inflected, the tip 

 very acute. 



Head rather large, oblong ; neck of moderate length and thick ; body 

 rather slender ; feet short, stout. Tibia bare for a considerable space ; 

 tarsus short, roundish, covered all round with small scales ; first toe very 

 small, third longest, fourth a Little shorter, the anterior connected by re- 

 ticulated webs having an incurved margin ; claws slightly curved, com- 

 pressed, acute, that of hind toe smallest, of middle toe by much the largest, 

 and having the inner edge thin and dilated. 



Plumage soft, close, blended, very short on the fore part of the head 

 elongated behind, rather compact on the back and wings. Wings ex- 

 tremely long, narrow, and pointed ; primary quills tapering but rounded, 

 the first longest, the rest rapidly graduated ; secondary short, rather nar- 

 row, tapering, rounded. Tail long, deeply forked, of twelve feathers, of 

 which the outer taper to a rounded point. 



Bill bright carmine, the tips paler. Iris dark brown. Feet black. 

 The top of the head and occiput is greenish black ; the back and wings 

 light greyish-blue ; the primary quills bluish-grey on their outer webs, 

 darker on the outer part of the inner, their inner part white, as are the 

 ends and inner webs of the secondaries ; upper tail-coverts and tail grey- 

 ish-white ; all the other parts are pure white. 



Length to end of tail 19 inches, to end of wings 20| ; extent of 

 wings 44 ; wing from flexure 15 ; tail 7 ; bill along the back 2|, along the 

 edge of lower mandible 1{^ ; tarsus 3i% ; middle toe 1, its claw ^. 

 Weight 14i oz. 



The figure of the Crab in the plate was introduced on account of its 

 singularly bright red colour, which, when the animal is boiled, changes 

 to pale yellow. It is rather common along the rocky shores of some of 

 the Florida Keys, and is excellent eating. 



