HYMENOPTERA. 213 



Pterygopuorus, Kliig., 



Where the antennae, have but a single range of teeth, and simply 

 longer or pectinated in the males, and short and serrated in the fe- 

 males ; here they are evidently enlarged at the extremity *. 



L0PHYRUS,ia^., 



Where the antennae, in the males, have a double range of elon- 

 gated teeth forming a large triangular panache, and are serrated in 

 the females, 



To this subgenus I refer the first family of the Pterones of M. Ju- 

 rine, as well as the first division of the Hylotomce of Fabricius. The 

 larvae or pseudo-caterpillars live in society, more particularly on the 

 Pines. They are very injurious to the young plants f. 



There, the labrum is concealed or but slightly salient. The inner 

 side of the four posterior tibiae, anterior to its extremity, presents two 

 spines, and frequently even a third above the preceding jjair. The 

 antennae are always multiarticulated, the head is large, square, placed 

 on a little neck, and has strongly crossed mandibles. They appear 

 in spring. 



The larvae of the greater number are destitute of membranous 

 feet, and inhabit silken nests of their own spinning, formed round the 

 leaves of various trees. 



They constitute the genus Cephalcia of Jurine, which has been 

 divided into two. 



Megalodontes, Lat. — Tarpa, Fab., 



Where the the antennae are serrated or pectiniform \. 



Pamphilius, Lat. — Lyda, Fah., 



Where those organs are simple in both sexes. 



Their larvae are destitute of membranous feet, and the posterior 

 extremity of their body is terminated by two horns. They feed on 

 leaves, which they frequently double in order to remain concealed §. 



In the last of the Tenthredinetae, the ovipositor is prolonged be- 

 yond its groove and projects posteriorly. The inner extremity of the 

 two anterior tibiae presents distinctly but a single spine, curved and 

 terminated by two teeth. The antennae are always composed of a 

 great number of simple joints. 



Xyela, Dalm. — Pinicola, Breh. — Mastigocerus, Kliig. 



The Xyelee are very distinct by their geniculate antennas forming 

 a sort of whip, that are abruptly attenuated near their extremity, and 

 consist of eleven joints, the third of which is very long ; as well as by 



* See Klug, Leach, and Lepeletier, Ibid. 



t Lepelet., Ibid., and the Moaog. of this subgenus, published by Kliig, ia the 

 Mem. Nat. Cur. of Berlin. 



X See the preceding works, and the Entom. Monog., Kliig, p. 183. 



§ Ibid. Eucyc. Method., article PamphUie, and the Monograph of the genus 

 Lyda of Klug, in the Mem. Nat. Cur, of Berlin. See also the Monograph of M. 

 Lepeletier. 



