EXTERNAL ANATOMY OF INSECTS. 555 
by the prothorax. In some species of Reduvius (R. bi- 
guttatus, mutillarius, lugens, &c.) it is armed with one 
or more dorsal or terminal spines. In the Homopte- 
rous section, where the dorsolum, as in Cicada, is not 
covered by the prothorax, the scutellum, which is merely 
a continuation of that part, bears some resemblance to a 
St. Andrew’s cross, and terminates in a fork?; in Ful- 
gora, in which it is partly covered, it is merely the trian- 
gular point of the dorsolum; in the Cercopida, &c., whose 
dorsolum is wholly covered, the triangular scutellum is 
distinct from it; in Centrotus, Darnis, and Membracis, in 
which the prothoraz is producted, and covers the abdo- 
men more or less, the scuéellum is a short transverse di- 
stinct piece. In the Lepzdoptera, from the difficulty of 
abrading sufficiently the scales and hairs without injury, 
it is difficult to obtain a correct idea of the part in ques- 
tion; in the cabbage butterfly (Pontia Brassica) it ap- 
pears to be triangular: in the humming-bird hawk- 
moth (Macroglossa Stellatarum) it approaches to a rhom- 
boidal shape; and in the eggar-moth (Lasiocampa 
Quercus) it is completely rhomboidal. In the Lidellu- 
lina, in the Neuroptera Order, it seems to be represented 
by the posterior point of the dorsolum, which terminates 
in something like a St. Andrew’s cross. In most of 
the other tribes of this Order the scutellum is a triangu- 
lar piece, with the vertex to the head, received between 
two pieces of the dorsolum; in Psocus it is nearly like 
that of Cicada before described. In the Hymenoptera 
the scuwtellum is separated from the dorsolum, which it 
4 Prate VIII. Fic. 16. x’. 
> Prarte IX. Fic. 1. %’.. N.B. This is from Cossus F. 
© [bid, Fic. 7. &'. 
