19 07 J 
Bnics, XortJi Anievican Paraf<itiv Hyiticnoptcra. 
157 
FAMILY ICHNEUMONID^. 
Orthopelma thompsoni sp. nov. 
Male and female. Length 3.75-4.25 mm. Head and thorax black ; 
legs in part and p.bdomen beyoad the petiole reddish. Head broad, 
almost three times as wide as thick. Face distinctly narrowed below, 
more strongly so in the male. Clypeus with an impressed line near 
the anterior margin which is raised and weakly emarginate. Mandi- 
bles black, clypeus reddish in the male. Palpi pale. Antennae short 
and rather stout, 18-19-jointed in the female and 22-jointed in the 
male. Flagellar joints decreasing in length apically except the last, 
which is twice as long as the preceding; first flagellar joint four 
times as long as thick, penultimate only slightly longer than thick. 
Surface of head shining, faintly punctate, more distinctly so on the 
occiput and cheeks. Eyes bare, elongate, twice as long as wide. 
Occiput and cheeks margined behind. Mesonotum finely punctate, no 
trace of ])arapsidal furrows. Scutellum with a depression anteriorly 
and strongly convex posteriorly. jNIetanotum areolated, all the areas 
separated and distinct. Abdomen with a long petiole, which is at least 
four times as long as broad ; spiracles prominent, placed near the 
basal third ; its surface finely rugose, with a carina on each side from 
the spiracle nearly to the tip of the segment. Following segments 
polished. Ovipositor as long or a little longer than the abdominal 
petiole, reddish, its sheaths narrow, black and nearly bare. Meso- 
pleura polished, with a fovea near the center, margined behind and 
with a wide finely crenate furrow below. Legs moderately stout; 
pale ferruginous, hind femora except tij) piceous, and hind tibiae 
darker apically. Coxae and first joint of hind trochanters black. 
Tegulae pale yellow, abdomen, except petiole, brig'ht ferruginous, the 
segments often with darker spots laterally behind, es]>ecially in the 
male. Wings hyaline, stigma and veins piceous, the former broad and 
])aler at the base. Areolet open behind and small in position. 
Described from numerous specimens bred by Prof. M. T. 
Thompson from the galls of Rhodites rosw dX Worcester, Mass. 
Most of the known species of the genus are parasites of various 
members of the genus Rhodites, 
