402 SERBICOKNIA. 



Ten examples, four of which belong to the var. a. This very small species is allied 

 to A. suturalis, A.phedrus, &c. The typical, or spotted form, approaches the var. a of 

 A. suturalis. There is a specimen from Rio Janeiro in the Janson collection, from 

 that of Candeze, apparently belonging to the unicolorous variety. 



Group POMACHILIINI. 



PSILONISCUS. 



Psiloniscus, Candeze, Monogr. Elat. iii. p. 3 (1860) . 



Four species of this genus were described by Candeze, all from Mexico ; two of these 

 have an extended distribution within our limits, one reaching as far south as Ecuador. 

 An interesting new form is now added from Costa Rica. The males do not appear to 

 have been known to Candeze ; they have very long antennas, nearly or quite half the 

 length of the body. Our five species may be thus separated : — 



a. Apex of the elytra truncate, the outer angle dentiform. 



a'. Pubescence on the elytra forming more or less distinct spots. 



a". Prothorax with a space down the middle and two spots on either side 



of it impunctate ; hind angles bicarinate sticticus. 



b". Prothorax with a space down the middle only impunctate ; hind angles 



not carinate costaricensis. 



c". Prothorax uniformly punctured ; elytra inf uscate at the tip apicalis. 



b'. Pubescence on the elytra uniform borborurus. 



b. Apex of the elytra rounded brunneus. 



1. Psiloniscus sticticus. (Tab. XVI1L fig. 7, 6 .) 



Psiloniscus sticticus, Cand. Monogr. Elat. iii. p. 6 \ 



Hal. Mexico, Orizaba, Cordova (SalU x ), Misantla and Jalapa (Edge); Guatemala, 

 Coban in Vera Paz (Conradt), Sinanja and Senahu in Vera Paz, Cerro Zunil, Calderas, 

 Duenas, Capetillo (Champion) ; Nicaragua, Chontales (Belt) ; Costa Rica, Volcan de 

 Irazu (Rogers). 



This is the commonest species of the genus. The antennae are about half the length 

 of the body in the male, very much shorter in the female. The hind angles of the 

 thorax are distinctly bicarinate. The thorax is very irregularly punctured, a space 

 down the middle and two spots on either side of it being impunctate ; the elytra have 

 on the alternate interstices a series of impunctate glabrous spaces, in front of each of 

 which is an oblong cluster of pale hairs. A male from Cerro Zunil is figured. 



2. Psiloniscus costaricensis. (Tab. XVIII. fig. 8, $ .) 



Very elongate, narrow, shining : brownish-testaceous, the head with a spot on the vertex, the prothorax 

 with a broad median vitta, and the elytra with a patch at the shoulders, blackish-aeneous ; the 



