IOWA ACADEMY OF SCIENCES. 9|9 



It has not been thought best at present to change the generic 

 reference given by VanDuzee, although not included in the 

 synopsis. With a more exact definition of the American genera 

 which will be possible as our species are better known, this and 

 some other aberrant forms of a generalized and plastic charac 

 ter may find their proper position. 



It was first described by Forbes as a Cicadula from specimen* 

 with weak venation. VanDuzee received dark specimens of 

 the green form from Mississippi and described them as Tham- 

 notettir perpunctata: also describing a strong veined form from 

 California with two cross nervures as, D.fuscinervosus. Gillette 

 and Baker, from very dark forms, described D. vanduzei. 



Larvas and adults were found in immense numbers about the 

 first of July. The larvae had mostly all issued by the 10th, the 

 adults continuing through the month; adults were again taken 

 late in September and on into October. They were first found 

 on a patch of plowed ground overgrown with Panicum sangui- 

 nale and crus-galli, and Setaria viridis. Here they occurred in 

 immense numbers. They appeared to be more common on the 

 annuals than on the perennials, but were taken almost every- 

 where, the later ones mainly from blue grass, the annuals hav- 

 ing ripened and died. Professor Forbes described it as a seri- 

 ous pest of oats and in Insect Life, vol. VI,. it was recorded as 

 very abundant and destructive in lawn grass in Washington, D. C. 



Where first found this season it occurred in two distinct forms 

 about equally common, one with a single cross nervure and long 

 elytra as in Thamnotettix. This form was light greenish-yel- 

 low with a light face, usually surrounded by an arch of dots 

 above on the anterior margin of the vertex and two oblique 

 dots on the disk of the vertex. The other form was cinereus, 

 darker below, with shorter hyaline elytra, usually with two 

 cross nervures and the central anteapcal cell divided. These 

 may probably be regarded as the equivalents of long and short- 

 winged forms in other species, the smaller darker form with 

 the more complex venation, being found almost everywhere, 

 while the lighter form with the weak venation was only found 

 in connection with the larva? and apparently made little use of 

 the wings. 



The specific characters differ very little betvs'een the differ- 

 ent forms, the variations in geiiitalia being similar to those in 

 the long and short-winged forms of other species. 



The vertex is short, obtusely angled, margins rounding to the front; a 

 row of dark spots on the anterior margin extending down the face to the 

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