146 Trans. Acad. Sci. of St. Louis. 



elytra, the sides converging rapidly from base to apex and broadly 

 arcuate ; segments very short ; surface finely, densely punctulate and dull. 

 Male unknown; female with the sixth ventral narrow, transversely 

 truncate at tip. Length (contracted) 3.2 mm.; width 1.0 mm. Arizona. 



compacta n. so. 



There are other species of this genus in northern Mexico* 

 but I do not know of any additional from our own territories. 

 Acaloph ena was proposed by Dr. Sharp as a substitute 

 for the preoccupied name Calophaena Arrib., (Bol. Acad. 

 Nac.,vii, p. 270), founded upon the Argentine basalis Arrib. 

 The Mexican angularis Er. and the South American polita, 

 pagana, gtrmana and picta, of Sharp, included by Dr. Sharp, 

 differ greatly from the two species here described in their 

 slender form and relatively broader neck, and it is probable 

 that they will prove to be generically different. It is a re- 

 markable fact that compacta and horridula agree much more 

 closely with basalis — the type of the genus — than those 

 just mentioned. The very short compact form and unusual 

 facies of compacta and horridula, would seem to indicate 

 some specialized or restricted life habits, such for example as 

 a termitophilous symbiosis, which is also ascribed by Arribal- 

 zaga to the typical basalis, while angularis and the others 

 allied thereto, probably have habits not differing in any way 

 from those of Dacnochilus . 



LlTHOCHARES. 



The densely punctulate and dull sculpture, together with 

 certain habital features of this subtribe, gives to the species 

 a superficial similarity to the Medones — so much so that the 

 genus Lithocharis has been included by Hey den, Reitter and 



* One of these may be described as follows: — 



Form and structure throughout as in compacta but larger, pale tes- 

 taceous throughout, except the head and elytra which are black, the apex 

 of the latter very narrowly — but more broadly toward the sides — tes- 

 taceous; sculpture and tactile setae similar to thosa of compacta, the ab- 

 dominal punctulation less dense and with the surface shining, each segment 

 with a transverse median series of erect stiff setae not evident in compacta. 

 Length. 44 mm. ; width 1.2 mm. Mexico (Vera Cruz) horridnal n. sp. 



