56 



BRITISH ICHNEUMONS. 



[/?/2jssa. 



latter sometimes coalesce across the apex of the metathorax, white. 

 Scutcllum and postscutellum entirely or apically white ; very rarely black. 

 Abdomen quite twice longer than head and thorax, cylindrical and about 

 as broad as the latter, in 9 subcompressed laterally ; basal segment 

 gradually constricted, of (J thrice longer than broad, glabrous and cen- 

 trally canaliculate ; one or two basal segments apically, and laterally 

 towards the apex, white ; second or third to seventh with lateral and infra- 

 apical spots on either side more or less broadly white ; terebra nearly a 

 quarter again longer than the body. Legs elongate and somewhat slender, 

 fulvous ; coxae sometimes badious, or rarely in ^ black, front ones of 



9 very rarely nearly totally black, 

 the anterior in both sexes gener- 

 allv whitish beneath ; hind tarsi 

 and tibiae infuscate or rarely dull 

 ferrugineous. Wings narrow and 

 fiavescent, with the stigma nigre- 

 scent ; radix and tegulae white ; 

 areolet irregularly triangular, ses- 

 sile or subpt'tiolate ; first recur- 

 rent of lower wings stronglv 

 postfurcal and intercepted far 

 abo\e the centre. Length, 

 22-34 nim. 



The J is much the smaller and 

 more uncommon sex. 



Taschenberg, 1 believe, first 

 found this species to be parasitic 

 upon the blue Wood Wasp, Sircx 

 jurcncus ; and Vollenhoven gives 

 (Tijds. v. Ent. iv., p. 176, pi. xii.) 

 a short description in Dutch, with 

 figures, of the larva and pupa. 

 The former, he says, is 2.5 Dutch 

 duims in length, smooth and shin- 

 ing, with eighteen spiracles, each 

 of which stands in a little pit- 

 like depression with brown walls; 

 in the female pupa, the terebra is 

 reflexed and laid along the back, 

 that of the $ is eighteen and 

 that of the 9 nineteen to twenty- 

 two millimetres in length. 

 Rhyssac are found flying in pine woods, ^\•here the larvae of Siriccs attack 

 the solid timber, boring tunnels through the wood, as does the Goat Moth 

 in deciduous trees. It is still a moot point Axhether R. pcrsiiasoria 

 reaches these larvae by intruding its long terebra along the victims' bur- 

 rows or actually, in propria persona, bores through the bark and solid wood 

 to her prey. Fred. Smith exhibited a 9 which " appeared " to have 

 worked its ovipositor, bradawl -fash ion, through a piece of fir wood ; and 

 Bond said that, at Bournemouth, he had found two of these ichneumons, 

 with their ovipositors so firmly fixed in the wood that he could not remove 

 them {cf. jNIeeting, Ent. Soc. April ist, 1867, ti E. M. M. 1865, p. 278). 

 Gravenhorst tells us (/.t.) that he found a 9 "-^^ Mount Zobten, in Silesia, 



