HOMOPTERA. — APHID. 44.) 
are shorter than in the true Aphides. Other species agreeing with 
Lachnus lanigerus in the neuration of the wings, have the body naked and 
the wings in repose carried flat upon the body. I possess three small Bri- 
tish species of this group. The very large species which Mr. Haliday 
has conjectured is identical with Phylloxera, found by Réaumur in the 
crevices of the oak, and figured by him (Mém. tom. iii. pl. 28. f. 5—14.) 
(Lachnus Quercus Burmeister) agrees with these in the wings being 
carried flat upon the body, and the body destitute of tubercles ; but 
the apterous individuals are naked, and have the promuscis nearly 
three times as long as the body beneath which it is extended in re- 
pose, reaching far beyond its extremity like a tail: from the greatly 
magnified figures of this instrument given by Réaumur, this instru- 
ment appears evidently 4-jointed, the penultimate joint being thickened 
and the preceding joint being capable of great contraction. The genus 
Phylloxera Fonsc. differs from the preceding in having still fewer nerves 
in the wings (only three simple ones upon the disc of the wing), al- 
though these organs are carried flat upon the back. M. Fonscolombe 
has sent me a specimen of the species found by him on the Elza an- 
gustifolia (Ann. Soc. Ent. France, 1834, p. 224.), with the expression 
that it certainly belongs to his genus Phylloxera; and M. V. Audouin 
has supplied me with both sexes of the species found on the oak. The 
very minute species Vacuna coccinea of Van Heyden (to whom I am 
indebted for specimens) has the wings similarly veined. The ge- 
nera Paracletus and Forda V. H. (which I also possess from their 
talented describer), as well as his g. Trama, are founded upon minute 
species which reside in ants’ nests.* (Réaumur also mentions finding 
Aphides in the nests of these insects.) These insects are all apterous 
as well as the genera Rhizobius Burm., and Atheroides Hlaliday. The 
last-named author has published some interesting observations on the 
habits of the species of Eriosoma in the Annals of Nat. Hist., Nov. ‘ 
1838+, the majority of the species of which are produced within 
* JT have above (p. 229. and 234. ), alluded to the fondness of ants for the saccha- 
rine matter secreted by the Aphides, the place of which seems supplied in tropical 
climates by the more numerous species of Centrotus and allied genera. 
+ In Risso’s Hist. Nat. de ? Europe Mérid., tom. v. 1826, two new genera are in- 
dicated by Leach, namely, Doralis (sp. Pini Leach, Dauci F., Ulmi Le., and Ru- 
micis Le.) and Phalaris (sp. Cerasi Le., Absinthii Le., Salicis Le., Vitis Le., Populi 
Le., and Tanaceti Le.), without any characters; and a new species of Eriosoma is 
described under the name of E. Olez. I do not know the genus Adelges Vallot. 
