SUCTORIAL ANIMALS. 263 



upon insects, but lizards and other reptiles ; and Azara 

 asserts that the Saurophagus sulphuratus or Bentevi 

 fly-catcher of Brazil, actually picks the meat from 

 the bones of such carcasses as have been left by the 

 larger animals of prey. Such facts are highly 

 interesting, and will frequently, as in the bird last 

 mentioned, decide a doubtful point in natural ar- 

 rangement: it follows, therefore, that omnivorous 

 habits furnish characters of great value. 



(181.) There is another mode of taking food, 

 very general among the invertebrated animals, but 

 not so distinctly marked in the higher classes. We 

 allude to suction, by which fluids alone constitute 

 the sustenance of the animal. There is a modi- 

 fication of this structure of mouth in the ant-eaters, 

 and in the honey-sucking birds (Tenuirostres), 

 where the tongue alone is employed to collect food ; 

 but the most perfect examples of the suctorial 

 structure of mouth are found among the four- 

 winged insects, where we find two entire orders, — 

 the Lepidoptera and the Hemiptera, — entirely 

 destitute of jaws, and deriving their sole nourish- 

 ment from juices, sucked up either by a slender 

 jointed trunk, or a long and spirally rolled pro- 

 boscis. Nature has evidently made this structure 

 a leading distinction of particular groups through- 

 out the animal circle, for we find that in every 

 class some are suctorial, while others are not; and 

 that this habit is always accompanied by a uni- 

 formity in the general shape of the rostrum or 

 mouth, which, as suited to such functions, is always 

 very long and slender. This we see in the ant-eaters, 

 s 4 



