86 bulletin: museum of comparative zoology. 



Described from one specimen sent by Professor Cockerell, No. A66. 

 Type in the Amer. Mus. Nat. Hist. 



Mesochorus revocatus, sp. nov. (Fig. 67.) 



Length probably about 8 mm., although only part of the head and thorax 



and the wings are preserved. The metanotum is regularly areolated, with the 



basal and middle lateral areas sepa- 

 rated. The wings are hyaline, with 

 fuscous veins and stigma. Stigma 

 long, lanceolate. Marginal cell mod- 

 erately long, the second section of 

 the radius straight, twice as long as 



Fig. 67.— Mesochorus revocatus, sp. the first; areolet moderately large, 

 nov. Type. with a long petiole above; obliquely 



rhomboidal in form; discocubital cell 



short, the submedian cell scarcely longer than the median. General color 



of body black. 



Type.— No. 2277, M. C. Z., Florissant, Col. (No. 14,494, S. H. 

 Scudder Coll.). 



Mesochorus terrosus, sp. nov. 



Female. Length 6.5 mm. Black; antennae and abdomen beyond the 

 second segment, brown. Head small, antennae long and slender, the basal 

 flagellar joints four or five times as long as thick. Metanotum regularly areo- 

 lated, the basal and middle lateral areas completely separated. Abdomen 

 clavate, the petiole stout, curved above but straight below, as long on its 

 dorsal surface as the second segment ; third to sixth segments gradually higher 

 dorsoventrally, but of about equal length. Ovipositor distinctly exserted, 

 its sheaths broad. Legs slender, brown or dark ferruginous, the tips of the 

 hind tibiae and the hind tarsi blackish. Wings hyaline; stigma and veins 

 ferruginous; marginal cell long, its second section straight, more than twice 

 as long as the first which is curved and longer than the thickness of the stigma. 

 Areolet moderately large; obliquely rhomboidal, subpetiolate above; disco- 

 cubital cell short, the discocubital nervure very sharply bent downward basally ; 

 submedian cell very slightly longer than the median. 



Type.— No. 2278, M. C. Z., Florissant, Col. (S. H. Scudder Coll.). 



Mesochorus cataclysmi, sp. nov. (Fig. 68.) 



Female. Length 5-7 mm. More or less brownish, the head and thorax 

 darker and the abdomen darker on the apical parts of the segments. Legs 



