49. 

 TRICHIOSOMA LATERALE. 



Order Hymenoptera. Fam. Tenthredinidse Lat., Leach. 

 Type of tlie Genus Tenthredo Lucoriim Linn. 



Triciiiosoma L^ach. Cimbex Oliv., Fab., Lat. Tenthredo Linn., 

 Fab., Jiir. 



Antenna inserted between the eyes, clavate, punctured, 7-jointcd, 

 first joint nearly globose, very hairj', second transverse, third very 

 long and slender, fourth and fifth clavate, truncate, sixth dilated 

 anteriorly, forming the base of the club which has an elevated 

 transverse suture, (f. 1.) 



Labrum quadrate, angulated at the base, rounded before and cili- 

 ated, sliglitly produced in the centre. (2.) 



Mandibles cxsertcd, of the male very long, slender, acute, most 

 commonly with two teeth on the internal side. (3.) 

 Maxillfe witli the external lobe corneous, the internal one mem- 

 branaceous, haiiy : Palpi irregular, extending a little beyond 

 the maxillic, composed of six joints nearly equal in length, the 

 fourth being the most dilated, and the tenuinal most slender. 

 (4.) 



Mentum short, oblong, slightly angulated before (5. a.) ; Palpi 

 a little longer than the lip, 4-joiiited, first and second joints 

 somewhat long, cyliudric, third joint membranaceous, flat, broad, 

 terminal joint slender, cylindric (b.) : Lip membranaceous, three- 

 lol)ed, the centre lobe rather the smallest, attenuated towards the 

 base, (c.) 

 Clypeus broad, slighthj emarginate. Ocelli 3. Abdomen sessile, villose, 

 cylindric in the nudes, sonmchat ovate and depressed in the females, 

 Jirst seyraent, especially of the males, slightly emarginate above. Ovi- 

 duct not exserted, composed of two lamella;, which are serrated. Supe- 

 rior wings with 2 maryiiud and 3 submarginal cells. Thiglis 4 

 posterior, dent a ted and incrassated in the males. Tibia" ?cith siphon- 

 formed spurs, obtuse at the apex. Tarsi 5 -jointed, with the penulti- 

 mate Joint a little shorter than the antepemdtiMate, four first joints 

 with small membranaceous appendages, dentated beneath, especially the 

 first joint of the males. Claws simple (Sfore leg of a mciW). 

 Larva with membranaceous feet. 



Latekale Leach Zool. Mis. v. S. p. 109. n. 2. 



.^llneous black covered with soft yellowish hairs. Head and anten- 

 nae very black ; sides and underside of abdomen, tibise, tarsi, and 

 costa, yellow inclining to ferruginous. Wings stained with yellow, 

 posterior margin fuscous. 



Li the Author s and other Cabinets. 



The Genus Trichiosoma was established by Dr. Leach in his 

 valuable Monograph upon the Tenthredinida : it is closely allied 



