1864.] 305 



Male. — Resembles the female, but much slenderer, the antennae is 

 more or less yellowish or whitish beneath, the four anterior coxae are 

 white, as well as the posterior tarsi except extreme tips ; the abdomen 

 much more elongate and subcylindric, the basal segment mostly all 

 black, linear, with a projection on each side behind the middle, the 

 2nd, 3rd and most of the 4th segments are rufous, the 7th, and some- 

 times the 6th, segment has a rounded white spot above. Length 4j 

 lines ; expanse of wings 7 lines. 



Hah. — Mass. (Sanborn); Penn. (Auxer); Delaware (Dr. Wilson). 



This is closely allied to C. nuncius Say, but is at once distinguished 

 from that species by having the white spot or spots on the apex of the 

 abdomen, otherwise they are very similar. 



22. Cryptus ultimus, n. sp. 



Black; the legs and four basal segments of the abdomen pale rufous, rest of 

 the abdomen black except a large white spot on the seventh segment: wings 

 subhyaline; ovipositor nearly as long as the abdomen. 



Fcmalr. — Black, shining, robust; head short and broad, entirely 

 black; antenna? rather more than half the length of the body, brown- 

 black, black at base, the 3rd and 4th joints long and subequal, 5th 

 shorter, 6th shorter than the 5th. Thorax densely and finely punc- 

 tured, opa<(ue, the dorsal lines not deep; scutellum polished; meta- 

 thorax densely punctured, opaque, the elevated lines tolerably well 

 defined, the lateral tubercles small, acute. Wings slightly tinged with 

 fuscous; uervures and stigma pale fuscous; areolet large, subquadrate 

 or 5-angular, the lower nervure broadly angular, the outer nervure 

 rather shorter than the inner nervure. Legs pale rufous, tips of the 

 four posterior femora and of their tibit>3, black. Abdomen robust, ovate, 

 pale rufous, shining; basal segment arcuated, broad at tip, slender at 

 base, polished; the 5th and apical segments black, polished, the seventh 

 segment above with a large white spot posteriorly, the fourth segment 

 above is somewhat stained with blackish posteriorly ; ovipositor nearly 

 as long as the abdomen, rufous, valves black. Length 4 lines; ex- 

 panse of wings 6 lines. 



Hah. — Rocky Mountains, Colorado Territory. 



(Closely allied to C. extrematls^ but readily distinguished by its much 

 shorter and entirely black antennae and by the coloring of the posterior 

 legs. 



