44 INTERNAL ANATOMY OF INSECTS. 
as in Gryllotalpa : or between them and the prothorax, 
as in Blatta: in the Hemzptera and Neuroptera proper 
bly the situation is not very different. In the Lepidop- 
tera this pair of spiracles is planted just before the base 
of the upper or primary wings*: a similar situation, I 
suspect, is appropriated to it in the Trichoptera, ei co- 
vered by a tubercle or scale. Something similar has 
been noticed by M. Chabrier, in the same situation and 
circumstances, in the collar of Hymenoptera>. In nu- 
merous Diptera this breathing pore is planted on each 
side between the collar and the dorsolum above the 
arms°, and in Hippobosca in the collar itself. 
In Lepidopterous, Coleopterous, and some other larve, 
the two segments of the body corresponding with the 
alitrunk in the perfect insect, are without spiracles, nei- 
ther have they in this state, though pneumatic organs 
have been discovered *, any real ones in that part: but 
not so the remaining orders, all of which have these or- 
gans in that section of the trunk. To begin with the 
Orthoptera :—in Blatta there seems to be a long narrow 
one behind the intermediate leg; in the Gryllotalpa there 
is one in the posterior part of the pleura ; and in Lo- 
custa Leach, above both the intermediate and hind legs f. 
It is probable, that in general those that have no spira- 
cles in the manitrunk have four in the alitrunk, which 
seems the natural number belonging to the trunk. In 
many of the Heteropterous Hemiptera in the parapleura 
* De Geer, i. 81. 4. v. f. 10. f. ® Sur le Vol des Ins. c.i. 459, 
© Reaum. iv. 246. ¢. xix. f. 8. s. 
4 In this tribe, which I forgot to remark before (see Vot. III. 
p- 551—.) there seems both prothorax and collar. . 
© Vou. IIT. p. 552, 562. &c. 
f Pray VIIL. Fie. 14, h”, n”, 
