18 O. C. DAVIS. 



parasitic even on other orders as Vanvollenhoven refers to Tischbein, 

 who bred a specimen from the coleopterons hirva of AdimonUi rus- 

 fica, and Reissig, the same species from a Tortrices. 



All specimens having- the distinctively characteristic teeth, spoken 

 of above, were first classified nnder the genus Bissus by Falliu in 

 1813, although it is true that the name had already been used by 

 Fabricius in 1804 in the " System a Piezatorum," but with a far 

 more general and indefinite classification. In 1868, Foerster, after 

 years of work and study on the Ichneumonidie, wrote a synopsis of 

 the family in which he made the old genus Bassns a family, and still 

 further restricted the genus BasKus as one of the genera in this 

 familv. His family Bassidie, or what is now considered a tribe in 

 other orders, is represented by ten different genera, six of which are 

 found in our American fauna. The characters used are plain, easy 

 to determine, and will greatly ail in a further and closer classification 

 of our old genus Bassus. 

 His synopsis is as follow's : 



The basal segment of abdomeu with a cross suture 1. Bassus Grav. 



The basal segment of abdomen without a cross suture. 

 Wings without areolet. 

 Face perfectly smooth. 



Antennae with more than twenty joints 2. PrometliUS Foers. 



Antenuie with twenty joints or less. 



CljTJeus very broad, the spiracles of the same seiuirated farther tlian the 



margins of the eyes . - 3. Bioblapsis Foers. 



Clyi^eus not very broad, the spiracles not separated farther than the mar- 

 gins of the eyes 4. liiopsis Foers. 



Face finely shagreened. 



Metanotum more or less areolated 5. Zootrephes Foers. 



Metanotum not areolated (j. Syrphoctouus Foers. 



Wings with an areolet. 

 Metanotum areolated. 



The longer spur of the hind tibiae extending half the length of the first 



tarsal joint 7. Aiiiarophron Foers. 



The longer spur of the hind tibiae not extending half the length of the 



first tarsal joint 8. Plitlioriiiia Foers. 



Metanotum not areolated. 



Base of second segment bicarinate, venter of the same indented. 



9. Enizemuiu Foers. 

 Base of the second segment without ridge, venter of the same not indented. 



10. Homotropus Foers. 



It is somewhat surprising at the number of synonyms found in 

 monographing the tribe. These are mostly due to the great difference 

 in color markings of the sexes, the male and female of the same 



