1864.] 297 



line, iridesceiat ; nervures and stigma pale fuscous, yellowish at base ; 

 areolet large, subquadrate. Legs pale rufous, the four anterior trochan- 

 ters, pale yellowish, their coxse somewhat tinged with yellowish ; tips 

 of posterior femora black, their tibiae, except base which is pale, and 

 their tarsi, dusky. Abdomen elongate, slender, subclavate, pale rufous, 

 shining; basal segment slightly arcuated, polished, with a tubercle on 

 each side of the apical third ; basal half of 2nd, basal margins of the 

 3rd and 5th, and the three apical segments, except an obscure whitish 

 spot on the 7th segment above, black. Length 3 lines ; expanse of 

 wings 5 lines. 



i/ai.— Delaware. Dr. Thos. B. Wilson. 



Closely allied to C. iridescens, but the antennae are longer, the areo- 

 let of the wings larger, and the abdomen and legs diiferently colored. 



Section 4. 

 11. Cryptus americanus. n. sp. 



Black; abdomen rufous; wings subhyaline; opivositor as long as the body. 



Female. — Black ; apical margin of the clypeus and the frontal orbits, 

 obsoletely whitish; face minutely punctured, much depressed just be- 

 hind the insertion of the antenufe, and finely and transversely aciculate ; 

 between the clypeus and the antennae there is a small rounded obtuse 

 tubercle ; palpi pale fuscous ; antennae nearly as long as the body, 

 very slender, curved at the apex, piceous, the basal joint robust, black, 

 the 3rd and 4th joints nearly equal in length, the 3rd longest, the 5th 

 joint shorter than the 4th, 6th about half the length of the 5th. Tho- 

 rax very densely and finely punctured; mesothorax with two deeply 

 impressed longitudinal lines, approximate posteriorly ; scutellum con- 

 vex, smooth and polished ; metathorax rugose, slightly pubescent, ab- 

 ruptly truncate behind, the lateral angles prominent, acute or subacute. 

 Wings subhyaline, more or less tinged with fuscous; nervures and 

 stigma black ; areolet 5-angular or somewhat triangular. Legs black, 

 shining; the four anterior tibiae and tarsi rufo-piceous, the posterior 

 pair piceous. Abdomen oblong-ovate, bright rufous, shining ; the basal 

 segment arcuated, broad at tip, smooth and polished, with a shallow 

 longitudinal groove on each side; ovipositor as long as the abdomen, 

 rufo-piceous, valves black. Length 3-6 lines ; expanse of wings 5-10 lines. 



Hub. — Delaware (Dr. Wilson); Illinois (Dr. Lewis). 



This species varies much in size. 



