178 



little darker tban head and thorax, the scape yellowish below ; face below antennae, 

 and a narrow baud around eyes (sometimes obsolete above) gamboge yellow ; eyes 

 black or dark brown. Thorax darker above than below; mesoscutuni with three 

 broad indistinct darker longitudinal bands, which vary considerably in intensity, 

 rather sparsely punctate, slightly shining, with a very faint median longitudinal sul- 

 cus ; mesoscutellum usually rather lighter in color than scutum, more densely punct- 

 ate, opaque ; metauotum varying considerably in intensity of color, very rugose, the 

 irregular carinte which produce the rugosity nluch darker than the intervening 

 spaces, a very shallow median longitudinal groove ; legs, especially tibiae and tarsi, 

 lighter in color than thorax; front trochanters sometimes quite yellow ; first joint of 

 hind tarsi fully five times as long as second joint ; wings uniformly dark fuliginous, 

 with a bronze reflection; teguhe concolorous with rest of mesoscutum. Abdomen 

 with petiole, concolorous with thorax ; joint 2 with a black stripe above, reddish- 

 brow below ; joints 3 to 7 dusky, nearly black, with a bronzy or purplish sheen ; lighter 

 on ventral line ; outer sheaths of ovipositor lanceolate, black except at immediate base 

 and strongly pilose. 



Eight $ specimens from pupai of Datana iniegerrima. 



Differs at a glance from the only other North American species of the genus, viz: 

 H. flavicornis BruUe and H. longijjcs Provaucher. 



! 



Fig. 39. — Tremex columba. a, larva, showing Thalessa larva attached to its side; 6, head of larva, 

 front view, enlarged; c, female pupa, ventral view ; d, male pupa, vential view ; f, adult female— all 

 slightly enlarged (original). 



In reference to the transformations of Thalessa our figures will suffi 

 ciently illustrate them so that there is not much need of a further remark 

 The larva (Plate I, a), as will be seen, has the ordinary Ichueumonid form 

 tapering at both ends, and has the typical parasitic jaws (/>) quite iucapa 

 ble of gnawing through wood. The spiracles are normally arranged 

 The most interesting ieature of the adolescent stages is the pupa in which 

 the long ovipositor extends at first in a direct line from the point of in- 



