103 
|t 
n is of this Aphis, and not of Siphonophora fragarice. In the 
'.nee of specimens of the winged forms, I have not ventured to 
a name to this species, especially as I am in doubt whether it 
lid be regarded as a root form, properly so-called, or whether it 
n aerial plant-louse, which had simply resorted to the crown at 
season for protection and reproduction.* 
here describe and figure this form, merely for the purpose of 
sequent identification. 
bis is a short [ovate plant-louse, with short five-jointedt anten- 
not on tubercles; a thick, prominent tail, and straight, cylin- 
al, slightly tapering honey-tubes. 
be general color is a dark, bluish green. The basal joints of 
antennae, the legs, the honey-tubes, and the tail, are yellow; the 
1 yellow or green. The tips of the honey-tubes, the tarsi, the 
>-femoral articulations, and the distal joints of the antennae are 
:. Young specimens are pale green throughout. 
ie body of an adult is about .1 mm. in length, by three-fourths 
vide. The honey-tubes measure .2 mm., the tail .1 mm., and 
antennae .8 mm. The third joint of the antennae is about twice 
i.ong as the fourth, the basal part of the fifth being a little 
ter than the latter, and its filament about three times as long. 
(l^v ■ ) 
NATURAL ENEMIES. 
.1 the plant-lice agree in being peculiarly susceptible to attack 
i. variety of enemies,—minute parasitic Hymenoptera, chiefly of 
genus Aphidius, the larvae of Syrphus flies, and many species 
idy-bugs (Coccinellidae), both in the adult and larval stages. 
have already remarked the parasitism of the species last de- 
; >ed, and Siphonophora minor was not less subject to this kind 
■ttack. Indeed, even the specimens kept in the breeding cages 
ughout the summer, were many of them killed by parasites be- 
autumn. 
lese insect enemies are frequently rather slow in concentrating 
ittack, the lady-bugs and the Syrphus flies not usually com- 
ciug to reproduce until the spriug is well over, and the para- 
Hymenoptera not commonly becoming numerous enough to 
; e any decided impression upon the host species until the latter 
) themselves appeared for some time in destructive numbers. It 
——— 
t is worthy of remark that many even of these partially subterranean individuals 
een recently parasitized, showing that their hymenopterous enemies follow them 
r the surface. 
decline to call the thread-like terminal part of the last joint of the antennae, com- 
o many plant-lice, a separate article. The fact that it is really continuous with the 
?r basal portion is of easy observation, the two parts being separated only by a 
sensory pore, beyond which the joint suddenly narrows. I see no sufficient reason 
isrepresenting the facts by considering this an articulation, especially as in some 
(like Schizoneura panicola) the terminal filament is reduced to a short thick lobe, 
i is not then called an article. 
& 
