food of gaily-coloured Caterpillars. 207 



taste, or by unwholesomenegs if eaten, and that their 

 remarkable coloration instead of being an attraction to 

 birds serves as a Avaruing. The late Mr. E. Newman, 

 indeed, remarks that, in the neighbonrhood of Barnstaple, 

 the only English locality where this catei'pillar is found 

 in numbers, it is devoured by sea-gulls and terns. This 

 fact, however, does not disprove the nauseousness of the 

 caterpillar, nor its protection against ordinary insectivo- 

 rous birds. Sea-gulls are by no means nice in their 

 tastes. 



It may not be out of place to remark that a vast field 

 of research lies open in ascertaining the connection be- 

 tween the food of an animal and the odour, flavour and 

 physiological action of its flesh, if eaten. Insects espe- 

 cially, from the colouring matters, the powerful scents, 

 and the poisons which they elaborate, present a multitude 

 of unsolved questions. Investigations of this nature be- 

 long, indeed, rather to chemistry than to entomology, but 

 they would nevertheless throw much hght upon a variety 

 of entomological topics. 



But the larvfe of the three hawk-moths just mentioned 

 are not singular in combining a conspicuous coloration 

 with a diet which, fi-om a human point of vieAv, must be 

 pronouiTced poisonous. The king of European haAvk- 

 moths, Chverocampa Nerii, is another instance. The 

 caterpillar is green, spotted with white, the tAvo first seg- 

 ments being of a lemon-yelloAv, Avhilst the third bears two 

 Avhite spots surrounded AA^th bright blue, and beyond this 

 Avith black. At the fifth segment begins on each side a 

 Avhite band leading to the tail-horn, often bordered Avith 

 blue in its hinder portion, and accompanied both above 

 and beloAv Avith an irregular number of white spots. The 

 oleander, its food-plant, notAvithstanding the beauty of its 

 floAvers and its exquisite perfume, is knoAvn to be poi- 

 sonous. 



Again, the caterpillar of the privet-hawk, too Avell 

 knoAvn to need description, must be admitted to be con- 

 spicuous, and its food-plants, the privet and the laurel, are 

 both poisonous. 



In contrast Avith the caterpillars aboA'e mentioned Ave 

 may take those of the lime- poplar- and oak-haAvks, the 

 eyed-haAvk, the large and small elephants, and the unicorn- 

 haAvk. All these feed upon plants not poisonous, and are 

 accordingly less conspicuously coloured. On the other 



