240 IOWA ACADEMY OF SCIENCES. 



Color the same as in the other forms, but in the specimens in hand the 

 lower part of head and under surface of abdomen is somewhat suffused with 

 rufous. The three powdery white bands on the elytra and the bright yel- 

 low across the clavus just back of the scutellum are very distinct. A spot 

 each side of the central yellow ocellus and the cuneus are more golden 

 brown than the rest of the elytra. The membrane is fuliginous except a 

 transverse band at base and a narrow margin to the cuneus which are 

 whitish transparent. 



Male: More slender, darker, head smaller and eyes more prominent. 

 Length 2 mm.; to tip of elytra 3.10 mm. 



Head nearly vertical, eyes prominent, prothorax strongly declivous, 

 widening to humeral angle; scutellum triangular, similar to female. Elytra 

 long, narrower than in female and with the end of corium and base of cuneus 

 forming an obtuse angle. Abdomen slender, flattened, the sides nearly 

 parallel. 



Color, dark brown or chestnut, the lower part of head a little lighter or 

 tinged with rufous; the first and second joint of antennte are yellowish and 

 the spot on dorsum back of scutellum is light yellow; the elytra are choco- 

 late brown with band inclosing the ocellate spot and the cuneus golden 

 brown; three broken whitish or pruinose bands across the elytra, the point 

 of scutellum and ocellate spot not quite reaching costal margin and the third 

 at base of cuneus represented by a triangular patch next the costa; mem- 

 brane as in the female; mesosternum piceous, polished, abdomen fuscous or 

 blackish, yellowish-brown at base, polished. 



Larvae taken with adults present similar characters, but are quite 

 remarkable in the greatly inflated terminal joint of the antennae. The 

 bodies are too much shriveled to permit of description. 



The macropterous females were collected May 28th andJune 

 7th, the brachypterous females May 22d, June 3d-7th and 12th, 

 and July 31st, the males June 2d-7th and July 28-29th. Larvae 

 July 28th. This indicates a rapid development of the larvae 

 between the 1st of June and the latter part of July and prob- 

 ably two broods for the year, but no rearing of the larvae or 

 exact limitation of the broods has been attempted. They occur 

 on grassy ridges in same location as preceding species. 



The significance to be attached to the peculiar dimorphism 

 and mimicry presented in this and the preceding species opens 

 a question of too far reaching importance to be discussed here. 

 That they resemble ants is certain, that they may- by this 

 resemblance gain some advantage is possible, but whether the 

 abortion of the wings and elytra is merely the result of such 

 mimicry or connected with advantages of an entirely different 

 nature we are not prepared to guess. I have used the term 

 mimicry in a general way to cover this feature of resemblance 

 but I would dissent from the use of this term in such a loose 

 manner if a better one were available. Such resemblances 



