148 BRITISH APHIDES. 



allusion was made to the same insect in another 

 number, under the name of Aphis holcl. 



This insect infests both these plants, but as Mr. 

 Hardy has seen them ovipositing on the Stellaria 

 holostea he prefers adopting that plant as a nominator 

 of the new species, since it would appear it there takes 

 its origin. 



The jS.gures of my plate were drawn from numerous 

 live specimens sent to me from Wooler, in North- 

 umberland, and from Penmanshiel Wood, in Berwick- 

 shire, in the month of August. The same competent 

 naturalist has since kindly furnished me with notes on 

 the economy of this Aphis, the substance of which I 

 here append. 



Mr. Hardy writes : " Aphis stellarice is eminently 

 social, and is not unworthy of the notice of the 

 vegetable physiologist from the parts of the plants in 

 which it nestles undergoing a fantastic disarrange- 

 ment. Its favourite plant is the stichwort, Stellaria 

 holostea and S. graminea, on which it is found within a 

 hollow pod fabricated from the leaves, each side of the 

 leaf being brought together above to form a canopy. 

 It checks the growth of the shoot in such a manner 

 that the leaves cluster into rigid tufts ; vegetable 

 irritation completes the structure. 



" During the summer it migrates from the stitch- 

 wort to one of the grasses, Holciis mollis. Here it 

 likewise revels in the centre of a tuft of leaves, for 

 these leaves, being prevented from receding, embrace 

 each other at their bases like those of a sedge. In 

 this manner a kind of boat is formed for the protec- 

 tion of the colony. In the autumn the Aphis reverts 

 to the Caryophillacese. 



" On the 4th of October I observed it on the 

 terminal shoots of Cerastium triviale, growing in the 

 dried-up channel of an upland rivulet, whose leaves 

 were similarly clustered in a boat-like form. The 

 females were then engaged in depositing their eggs — 

 minute, black, oblong-oval bodies. 



