— 18 — 



seem to me not of necessity mimicry in its proper sense, or 

 protective resemblance but merely the assumption of a similar 

 form by different animals when adapting themselves to similar 

 environments. The question readily broadens into a discussion 

 of all the factors of adaptive evolution and while attractive is 

 too large to attack in such a paper as this: 



PARAMESUS STRAMINEUS N. SP. 



Very similar to P. twiningi but of a light greenish-yellow color, the 

 dark band of elytra absent and the lower half of face light yellow. Length 

 to tip of elytra, female 5.50 mm., male 4.50 mm. 



Vertex rounded at apex, one-half longer at middle than next eye, ante- 

 rior two-fifths risinir to form a distinct, elevated, angular margin Front 

 sinuate next antennae then narrowing uniformly to base of clypeus; clypeus 

 twice as long as wide, widening to apex; gense sinuated below eye, scarcely 

 angular laterally, reaching clypeus by a narrow line; lorse elongate, angu- 

 lar at ends, twice as long as wide, their lower ends not reaching clypeus 

 by a considerable space. Pronotum minutely transversely rugulose on 

 posterior two-thirds, evenly arcuate in front, scarcely concave behind and 

 with a very shallow emargination near the middle, lateral margin short, 

 with a distinct carina, humeral margin distinct, rather short, angles sub- 

 prominent. Elytra with a few ramose nervures in clavus and between 

 second sector and claval suture. 



Color: Vertex, anterior two-fifths ivory white with two large, black, 

 angular transverse spots near middle and a smaller, irregular, lineate fus- 

 cous one each side near eyes; the posterior two-thirds uniformly greenish- 

 yellow or pallid with a longitudinal black impressed line at center. Face 

 dark in upper half and light in lower; a conspicuous black line from eye to 

 eye just below margin of vertex; front fuscous with light lines; clypeus 

 light fuscous; gense and lorte yellow, sutures black; pronotum greenish on 

 disk and posteriorly with bluish tint; front, margin, and sides more yellow- 

 ish, faintly mottled with irregular whitish maculations; scutellum ochre 

 yellow with whitish triangle on lateral margins and at tip, and a faint fus- 

 cous line separating the usual areas; elytra hyaline or pellucid with the few 

 ramose lines, a spot in the second, third and fourth apical, the middle and 

 inner anteapical cells, and an apical submargin, fuscous; apex of clavisand 

 costal transverse nervures dark fuscous or black; beneath light yellow 

 spotted and lined with black; tergum black with yellow maculate margin. 



Genitalia: Female, ultimate ventral segment long, posterior margin 

 broadly, shallowly excavated and bearing at center a ligulate process about 

 as long as wide and minutely notched at tip, pygofers posteriorly set with 

 minute remote short gray hairs arising from black points; male, valve very 

 short, scarcely visible; plates elongate triangular, reaching to tips of pygo- 

 fers, margins with a few hairs. 



Described from five females and one male. Of the females 

 two were collected at Sioux City, July 7th, one at Sioux Falls, 

 S. D., July 4th, and one at Ames, June 15th; and one collected 



