644. 

 MESOLEPTUS WALTONI. 



Order Hymenoptera. Fam. Ichneumonidse. 



Type of the Genus, Mesoleptus Isevigatus Grav. 

 Mesoleptus Grav., Curt. — Ichneumon, Bassus, Cryptus Fab. 



Antenna almost as long as the body, slender, slightly thickened 

 between the base and apex, inserted a little aboye the middle of 

 the face, rather remote, composed of 30 joints and upwards, 

 basal joint stout, 2nd somewhat cup-shaped, 3rd the longest, 

 4th oblong, the remainder decreasing in length to the apical 

 joint which is ovate -conic (1). 



Labrum concealed beneath the clypeus, transverse, the anterior 

 margin convex and ciliated with long bristles, having a mem- 

 branous pubescent trigonate lobe beneath (2). 

 Mandibles folding transversely, rather stout and cleft at the 

 apex, forming 2 subtrigonate teeth (3). 



Maxilla terminated by an ovate bristly lobe. Palpi long pube- 

 scent pilose and composed of 5 nearly equal joints, basal joint 

 elongated and clavate, 2nd a little longer and incrassated, 3rd 

 as long but not so stout, the following rather more slender (4), 

 Mentum long, gradually tapering to the base. Lip long and 

 broad. Palpi stout, longer than the lip, pubescent, bristly and 

 4-jointed, basal joint clavate, 2nd stout trapezate, 3rd pear- 

 shaped, 4th subfusiform (5). 

 Head transverse, face orbicular : eyes lateral ovate : ocelli 3 in a tri- 

 angle on the croivn of the head. Trunk long and narrow : scutel 

 semiovate : metathorax elongated, with elevated lines and a small 

 tooth on each side of the apex. Abdomen long depressed and clavate-^ 

 the petiole long slender and tuberculated on the sides : ovipositor 

 slightly exserted. Wings wz7/i an oblique somewhat ovate areolet (9)- 

 Legs, hinder the longest and stoutest : coxae hinder long and stout: 

 tibiae spurred at the apex : tarsi long and 5 -jointed, basal joint long, 

 4th and 5th very short : claws and pulvilli minute. 

 Obs. The dissections are taken from the species jigured. 



Waltoni Curt. Guide, Gen. 491. 57^. 



Black ; antennae with the joints vertebrate, the anterior margins 

 bristly (1), 3rd and a few succeeding joints fulvous; 2 vertical 

 ovate spots below the antennae, palpi and mandibles yellow, 

 apex of the latter ferruginous (1* the face) : petiole long slender 

 and channelled, dilated at the apex which is ferruginous, 3 fol- 

 lowing joints rufous ; areolet minute ovate oblique with a long 

 peduncle (9 b), nervures costa and stigma brown ; a portion of 

 the latter ochreous ; 4 anterior legs excepting the coxae and 

 trochanters testaceous, apical joint of tarsi brown, hinder tibiae 

 and tarsi brown, the former ferruginous at the base. 

 In the Author's Cabinet. 



Mesoleptus is a group detached from Tryplion by Graven- 

 horst : it contains 70 or 80 species, and about 50 have been 

 detected in this country. It is distinguished from Tryphon by 

 its long and slender petiole, and the areolet is generally of a 



