210 INSECTA. 
approximated and parallel, without a wide intermediate sulcus, form 
the genus 
Cimpex, Oliv. Fab.—Crasro, Geoff. 
The larve have but twenty-two feet. Some of them when irritated 
spurt a greenish liquor from the sides of their body to the distance 
of a foot. 
Dr. Leach *, by having recourse to the number of joints anterior 
to the club, their relative proportions and the arrangement of the 
cells of the wings, has divided the genus Cimbex into several others, 
one of which, Perea +, is peculiar to New Holland, and is distin- 
guished from all the others by the following characters. The four 
posterior tibiz have a movable spine on the middle of their inferior 
side. The scutellum is large and square, with its posterior angles 
projecting in the form of teeth. The valves that sheath the ovipositor 
are covered externally with numerous short and frizzled hairs. The 
antennz are very short, arid have six joints, the last of which, or the 
club, is without any vestiges of annulli as in Syzyconra, a genus 
established by Kliig on some species from Brazil}. The radial cell 
is appendiculated, and there are four cubital cells, the second and 
third of which receive, each, a recurrent nervure—the transverse 
nervures of the disk. 
M. Lepeletier de St. Fargeau, in an excellent Monograph of the 
Tenthredinete, only adopts the genus Perga, and in conjunction with 
him we will consider those of the English naturalist as simple divi- 
sions of Cimbex. 
The two following species belong to that number in which the 
antenne have five joints before before the club. 
C. lutea; Tenthredo lutea, L.; De Geer, Insect., II, xxxiii, 
8—16. About an inch in length; brown; antenne yellow; 
abdomen yellow, with violet-black bands. 
The larva, or pseudo-caterpillar, is of a deep yellow, with a 
blue stripe, edged with black along the back. On the Willow, 
Birch, &c. 
C. femoratu; Tenthredo femorata, Lat.; De Geer, Insect., II, 
xxxiv, ]—6. Large; black; antenne and ovipositor of a brown- 
yellow; blackish-brown spots on the posterior margin of the 
superior wings; posterior thighs very large, in one of the sexes 
at least. 
The larva lives also on the Willow; it is green, with three 
* Zool. Miscel., III, p. 100, et seq. 
+ Ibid., 116, cxlviii; Lepel., Monog. Tenthred., p. 40. 
~ Monog. Entom., p. 177; in the same work, p. 171, he gives the characters of 
another genus Pachglosticta, also peculiar to Brazil. The antenne consist of five 
joints. The superior wings are dilated near their extremity, and the callous point is 
semilunar. The second, third, and fourth joints of the posterior tarsi are very short. 
He mentions three species. 
The genus Perga, on account of the cells of the wings and the spines of the pos- 
terior tibia, should come directly before Hylotoma. 
