262 



VERTEBRATES. 



the toes are four in number, as in other swallows, three before and 

 one behind, and there is a little web or membrane filling half the 

 space betwixt the toes. In addition to this, it may be stated that 

 the bill is smooth, without any provision for breaking or grinding, 

 as the French would say, sans dentelu/res, and flattened alpng the 

 J J and the feet are short and small. Like other aquatic birds, 



The Sea Swallow. 



there is a small portion of the legs naked and without feathers, by 

 which tiiey are enabled to propel themselves with greater ease 

 through the watery element. The body is covered with down, 

 abundant and close. 



The family of the Sea Swallow is found both in Europe and 

 Asia, and also in the islands of the Pacific. In flying their cry is 

 acute and piercing ; in calm weather they sometimes elevate them- 

 gelves to an astonishing height, and before their migratory flights, 

 they assemble together in great multitudes. It is remarked, that 

 they are never so noisy and restless as at the time of building their 

 nests. They live on little fish and winged insects. 



The Esculent Swallow, whose nests are considered such 

 a delicacy among the-Chinese, builds its singular habitation iu the 



