INTERNAL ANATOMY OF INSECTS, 153: 
observing, with respect to the first of these insects, that in 
boring, as is the case with the Tettigonie and saw-flies, 
the motion of the valves was alternately backwards and 
forwards. It appeared also to me that the two outer 
pieces of each of the apparent valves were fixed in a 
groove in the margin of the intermediate one. I saw this 
clearly with respect to the upper pieces, and it is most 
probable that the lower are similarly circumstanced. In 
the cricket tribe (Gryllus Latr.) the ovipositor is as long 
as the abdomen, very slender, terminating in a knob?. 
It is apparently bivalve like that of Acrida, but I believe 
is resolvable into the same number of pieces. 
In the Homopterous Hemiptera there seems to be more 
than one type on which the ovipositor is constructed. In 
an insect very common with us, the froth froghopper (Cer- 
" copis spumaria), some approach is made to the ovipositors 
last described, at least the number of pieces is the same— 
for it has a pair of external valves forming a sheath, which 
includes three sharp /amine resembling the blades of a 
lancet, the middle one of which can be separated into 
two; this instrument De Geer had reason to think was 
scored transversely like a file. In the insects of this Or- 
der so noted for their song< ( Tettzgonza F.), there are only 
Jive pieces; namely, two valves forming the sheath, two 
augers or borers, and an intermediate piece upon which 
they slide, each being furnished with an internal groove 
for that purpose, and the middle piece with a ridge to 
fit; a contrivance of Divine Wisdom, to prevent their 
nects Conocephalus, Acrida, &c. with Locusta Leach, is also distin- 
guished by antenne at first filiform and then setaceous. 
* De Geer iii. ¢. xxiv. f£ 1, 12. » Ibid. 176. t. xi. f. 19. 
* Vor. IL. p. 394. 
