178 



little darker than liead and thorax, the scape yellowish below ; face below anteunae, 

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

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

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

 rather sparsely x^uuctate, slightly shining, with a very faint median longitudinal sul- 

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

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

 irregular carinaj which produce the rugosity much 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, 

 Tvith a bronze reflection; tegulse coucolorous with rest of mesoscutum. Abdomen 

 with petiole, coucolorous 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 9 specimens from pupse oi Datana integerrima. 



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

 H. flavicornis Brulle and H. longqjes Provancher. 



Fio. 39.— TliEMEX COLUMBA. a, larva, sliowinji Thalessa larva attached to its side : 6, head of larva, 

 front view, enlarged; c, femiile pupa, ventral view : d, male pupa, veutial view ; e, adult female-all 

 slifjlitly enlarged (original). 



In reference to the transformations of Thalessa onr fii;*ures will snili 

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

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

 tai)erin<^ at both ends, and has the typical parasitic jaws (/>) cpiite incapa 

 ble of ^nawin^^ throu*:^h wood. The spiracles are normally arranged 

 The most interesting- feature of the adolescent stages is the pupa in which 

 the lon^ ovipositor extends at first in a direct line from the i)oint of in 



