HEMIPTERA. 209 



This species cannot be identical with the willow-louse, Aphis 

 Salicis of Linnaeus, which has a spotted body ; and therefore 

 I propose to call it A])his Salicti, the plant-louse of willow 

 groves. When crushed, it communicates a stain of a reddish 

 or deep orange color. 



Some plant-lice live in the ground, and derive their nourish- 

 ment from the roots of plants. We annually lose many of 

 our herbaceous plants, if cultivated in a light soil, from the 

 exhausting attacks of these subterranean lice. Upon pulling 

 up China Asters, which seemed to be perishing from no visible 

 cause, I have found hundreds of little lice, of a white color, 

 closely clustered together on the roots. I could never discover 

 any of them that were winged, and therefore conclude from 

 this circumstance as well as from their peculiar situation, that 

 they never acquire wings. Whether these are of the same 

 species as the Aphis radicum of Europe, I cannot ascertain, 

 as no sufficient description of the latter has ever come to my 

 notice. These little lice are attended by ants, which generally 

 make their nests near the roots of the plants, so as to have 

 their milch kine, as the plant-lice have been called, within their 

 own habitations ; and, in consequence of the combined opera- 

 tions of the lice and the ants, the plants wither and prematurely 

 perish. When these subterranean lice are disturbed, the at- 

 tendant ants are thrown into the greatest confusion and alarm; 

 they carefully take up the lice which have fallen from the roots, 

 and convey them in their jaws into the deep recesses of their 

 nests; and here the lice still contrive to live upon the frag- 

 ments of the roots, left in the soil. It is stated * that the ants 

 bestow the same care and attention upon the root-lice as upon 

 their own offspring, that they defend them from the attacks of 

 other insects, and carry them about in their mouths to change 

 their pasture; and that they pay particular attention to the 

 eggs of the lice, frequently moistening them with their tongues, 

 and in fine weather bringing them to the surface of the nest 

 to give them the advantage of the sun. On the other hand, 

 the sweet fluid supplied in abundance by these lice forms the 



* See Kirby and Spence's Introduction to Entomology, Vol. II. pp. 91, 92. 

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