308 [Decembkr 



the chambers containing the hirvse of the ants, so that the consumers may 

 be as near as possible to the producers. If the flat stone covering the 

 nest, and studded with groups of the larvae of these jjemjjhigi, is carefully 

 replaced, and the nest revisited some hours afterwards, it is found that 

 they are generally most of them carried off. That this must be done by 

 the ants is proved by the fact, that the pemphigl show no disposition to 

 wander ofi", unless disturbed, and that if they are disturbed, the ants are 

 just as eager to carry them oflf to a place of safety as to carry off their own 

 larvae. On one occasion when the root of a tree happened to cross one of 

 the underground passage-ways constructed by the ants, I noticed upon it, 

 some inches below the surface of the earth, a cluster of these larvae ; which 

 proves that that species inhabits the roots of ti'ees and not those of her- 

 baceous plants. 



Pemphigus formicarius n. sp. 



Two kinds oi larvse occurred in company; the first, when recent, scarce- 

 ly twice as long as wide and whitish ; the second, when recent, three times 

 as long as wide and cinereous. From the latter I bred five wmgcd indi- 

 viduals, which differed as follows from the description of P. pt/ri Fitch :- 

 The size is somewhat smaller; the prothorax and abdomen of the living 

 insect are blue-black, pruinose, in the dried specimen pale yellowish-brown, 

 the abdomen much varied with fuscous; the thorax and head, both in the 

 living and dried insect, are opaque blue-black. Legs yellowish-fuscous. 

 Wings hyaline, slightly fumose at tip; veins not margined with broAvn ; 

 the 2nd discoidal is not more robust than the 1st and does not taper; the 

 costa and the anterior half of the stigma are very pale fuscous or cinereous, 

 the latter a little darker ; the posterior half of the stigma is black. In the 

 hind wings the apex of the black rib-vein or subcostal is nearly twice as 

 far from the apex of the 2nd discoidal as that is from the apex of the 1st 

 discoidal. 



Length to tip of wings .2 inch; expanse .33 inch. Five specimens. 

 The stigma is much hunched posteriorly, more acute at the basal than the 

 terminal end, and rather more than twice as long as wide. Bred Oct. 11th 

 from larvic found 8 or 10 days before in the nest of Formicd apliidicofa 

 mihi, attached to the root of what appeared to be a perennial herbaceous 

 plant. 



Pempliigus formicetorum n. sp. 



Diff'ers from P. pj/ri as follows: — The size is much smaller; the 2nd 

 discoidal is not more robust than the 1st, and is of uniform robustness 



