SCQDDER ON FOSSIL INSECTS. 743 



nearly rectangular; the anterior margin of the head is broadly and 

 pretty regularly rounded, and the whole head is of about equal length 

 and breadth. The thorax is very regularly ovate, broadest next the 

 insertion of the front wings (traces of the origin of which can be seen), 

 nearly twice as long as broad, rapidly tapering on the metathorax. The 

 X)eduncle, as seen from above, is square, half as broad as the head, the 

 hinder edge showing by its thickening that it was probably elevated at 

 this point. The abdomen is plump, rounded ovate, scarcely less rounded 

 posteriorly than in front, only one quarter longer than broad, broader 

 than the thorax, composed of six segments, of which the first, third, and 

 fourth are about equal in length, and the second half as long again. 

 Length of whole body 7.5"""; of thorax 3"™; breadth of same 1.8'"'"; 

 of peduncle CO'""" ; of abdomen 2.3'"" ; length of hind femora 4.3"'"" ; 

 breadth of same 0.3G™"\ Fossil Canon. 



On account of the smallness of the head, I venture to place this insect 

 in the genua Liometoimm. It has the aspect of a Hypodinea, but the 

 head is only half as broad as the thorax. 



Family Ichneumonid^. 



Ichneumon petrinus. — A fragmentary specimen, preserved on a dorsal 

 aspect; parts of the front wings, the thorax, and basal half of the abdo- 

 men are preserved. The body is blackish and the wing- veins testace, 

 ous; the wing, excepting the fusco-testaceous stigma, is hyaline, covered 

 sparsely with very delicate and moderately long hairs; the stigma is 

 long and slender, the heavier main portion about two and a half times 

 longer than broad, the slender basal extension as long again. Unfortu- 

 nately, the wing is preserved only so far as, but not including, the areola, 

 so that many characteristic parts are wanting; the second median and 

 first subcostal cells are united, the vein separating them being present 

 only below, where it is directed parallel to the principal longitudinal 

 veins; the vein from which it springs is bent at an angle of about 70°, 

 so that the part representing the first subcostal cell tapers rather rap- 

 idly in its apical half, while its basal half (if the cross-vein were con- 

 tinued) would be of the same size and shape as the second median cell- 

 or a parallelogram nearly twice as long as broad; the vein separating 

 the first and second median cells is continued in a nearly direct line 

 below; the third median cell is long and rather slender, with somewhat 

 produced angles basally. The first segment of the depressed abdomen 

 is fully half as long again as broad, increases a little and regularly in 

 size toward the extremity, at its base is about half as broad as the 

 extremity of the thorax, and at its tip less than half as broad as the 

 broadest part of the thorax; the second segment is considerably larger, 

 and also enlarges apically, but its length is indeterminate. Length of 

 thorax 2.6 """; breadth of same LS"""; length of wing to tip of stigma 

 4.2a™'"; breadth of base of abdomen 0.5""". Chagrin Valley. 



