BRUES: PARASITIC HYMENOPTERA. 33 



Key to the Florissant species of Ichneumon. 



1. Small, 6 mm. in length; areola of metanotum very small, nearly 



semicircular; antennae slender, all the joints much longer than 



wide; wings hyaline I. alpha, sp. nov. 



Larger species, 8-15 mm. in length 2. 



2. Wings hyaline, i. e. not or scarcely darker than the stone . 3. 

 Wings infuscated, much darker in color than the stone . . 8. 



3. Very large, 19-21 mm. in length I. pollens, sp. nov. 



Small or moderate in size, less than 15 mm 4. 



4. Second section of the radius nearly three times as long as the first 



(70 : 25) ■ ....■ I. obduratus, sp. nov. 



Second section of the radius approximately twice as long as the 



first I. primigenius, sp. nov. 



Second section of the radius one-half longer than the first 5. 



5. Discocubital vein with a stump of a vein near its centre . 6. 

 Discocubital vein simple, without any trace of a stump of a vein. 



I. deerepitus, sp. nov. 



6. Slender species, basal joints of antennal flagellum four or five 



times as long as thick 7. 



Stout species; basal flagellar joints not more than three times as 

 long as thick; abdomen not conspicuously banded. 



I. exesus, sp. nov. 



7. Areolet large, regularly pentangular . . /. torpefactus, sp. nov. 

 Areolet moderate, its radial side much shortened 



I. provectus, sp. nov. 

 Areolet small, regularly pentangular I. eannoni Cockerell, sp. nov. 



8. Large species, 15-18 mm I. dormitans, sp. nov. 



Smaller species, 12 mm. or less 9. 



9. Discocubital vein evenly curved; wings fulvous, body in part 



light colored I. concretus, sp. nov. 



Discocubital vein with trace of a stump of a vein ; wings blackish, 

 - body dark colored I. somniatus, sp. nov. 



Ichneumon alpha, sp. nov. 



Probably a male. Length 6.5 mm. Uniformly black or dark, the antennae 

 and part of the legs brown or fuscous. Wings hyaline. Head smooth or 

 microscopically sculptured, its surface opaque, strongly transverse in general 

 shape. Mesonotum subopaque, the parapsidal furrows rather distinctly 

 marked anteriorly by a line of punctate depressions. Scutellum very slightly 

 convex, with a crenulate transverse groove at its base and raised lateral 



