HYMENOPTERA. — TENTHREDINIDZE. 103 
These are very voracious, and shed their skins several times. When 
full grown, they descend into the ground, forming an oval cocoon of 
agglutinated earth, at the depth of several inches, the interior of which 
they plaster with a white shining secretion, and in which the earlier 
produced individuals remain but a short time; but the late broods do 
not make their appearance in the winged state till the following 
season. 
Hand-picking, and the employment of ducks to eat the grubs, are 
the most serviceable remedies hitherto suggested for the destruction 
of these obnoxious insects. 
Rusticus, in Hxtomol. Mag. vol. iii. p. 339.; Yarrell, in Trans. Zool. 
Soc. vol. il. p.67. pl.14.; Westwood, in Gardener's Mag. No.86. 
May, 1837; W.C., in Saturday Mag. vol. vi. p.181.; Curtis (Brit. 
Ent., October, 1836); W. W. Saunders, in Trans. Ent. Soe. vol. i. 
p. 76. App.; and especially Mr. Newport, in his admirably elaborate 
prize essay (1838), have given ample details of the history, &c., of this 
species. 
M. Brullé has published an account of the transformations of Cladius 
difformis Klug (Annal. Soc. Ent. de Fr. 1832, pl. 11. f. 11, 12.), the 
larva of which is found upon the leaves of Rosa centifolia and Ben- 
galensis. Curtis also reared this species from larvae found on the under 
side of the leaves of the China rose, eating small holes through them. 
Dahlbom once observed it upon Salix viminalis: it is slender, subcy- 
lindrical, clothed with slender upright hairs, and 20-footed. Curtis 
says that the anal feet do not assist them in walking. They are full- 
fed on the 28th of July, and the imago appears on the 11th or 12th 
of August, and they form a double cocoon of a very irregular shape 
amongst the leaves. Hartig has figured the larva and imago of 
Nematus (Pristiphorus) albipes, with numerous details (pl. 2. f. 16 
—26.). The larva is 20-footed, and closely resembles that of Cl. 
difformis; it feeds upon the under side of the leaves of the cherry. 
The larva of Nematus (Pristiphorus) Brullei Dahlb. (Priophorus B.) 
is very similar to the preceding, and inhabits the Rumex and Rubus 
fruticosus ; it is 20-footed, and forms a double cocoon, composed of a 
glutinous secretion, mixed with very fine silken threads. 
One of the most destructive insects in the family inhabits the goose- 
berry, upon which the larvae are found in society; from 50 to more 
than 1000 being sometimes observed upon a single tree, of which 
they devour all the leaves in the beginning of the summer, so that 
H 4 
