The Ohio Naturalist, 
PUBLISHED BY 
The Biological Club of the Ohio State University. 
Volume II, APRIL, 1902. No. 6. 
TABLE OF CONTENTS 
Osborn and Ball — North American Species of Athysanus 231 
Colton— A Possible Cause of Osars 257 
Kellerman and Jennings — Smut Infection Experiments 258 
Dufour — T railing and Creeping Plants of Ohio 261 
Kellerman— Corrected Description of Phyllosticta alcides 262 
Tyler— Meeting of the Biological Club 262 
A REVIEW OF THE NORTH AMERICAN SPECIES 
OF ATHYSANUS (JASSIDAE.) 
Herbert Osborn and E. D. Ball. 
The genus Athysanus Burm. is world wide in distribution and 
in many of the faunal areas is represented by a large number of 
species. Being one of the older Jassid genera it has like Dclto- 
cephalus been made the abiding place of a very heterogeneous mass 
of material. One by one the more strikingly distinct forms have 
been taken out and placed in genera of their own, leaving as a 
residue species whose strongest bond of union is probably their 
lack of distinctive generic characters upon which to separate them. 
As has already been suggested this confusion has been greatly 
augmented by the use of “ the second cross nervure” as a final 
test between this group and the Deltocephalinae. With every 
addition to our knowledge this character loses in value as a correct 
test of the separation of these groups and is now only regarded 
as of limited application between different genera in each series. 
Under such conditions it was found to be almost impossible to 
give any characters to the group that would apply to all the in- 
cluded species. An examination of a series from Europe showed 
that their fauna was even more complex than ours but that it 
would nearly all fall into the same groups and that most of the 
remaining species belonged to genera already set off in America. 
In the present paper an attempt has been made to arrange the 
North American species still remaining in this genus in a series of 
groups sufficiently homogeneous in character to be defined and 
thus give a basis upon which to work in future studies on related 
genera. In the following out of this plan a few species were elim- 
inated as more closely related to other genera and then it was 
found that the remainder could easily be arranged in four series 
