436 PHYTOPHAGA. 



strongly convex, and in this case generally brightly coloured and without pubescence. 

 The present division is not entirely confined to the New World, but has a few repre- 

 sentatives in Africa and Europe ; the species from these last-named countries form the 

 only exceptions to the striate punctuation of the elytra, the latter here being irregularly 

 punctured. For further particulars regarding the " (Edipodes " I must refer to Clark's 

 monograph, in which the figures are unfortunately uncoloured. A future monographer 

 of these insects will no doubt greatly reduce the number of genera established by 

 Clark ; in the present work remarks can only be offered on those which come under 

 examination, and so far as they refer to species inhabiting the regions under inves- 

 tigation. 



ALLOCHROMA. 



Allochroma, Clark, Cat. Halticidse, p. 181 (1860). 

 JExartematopus, Clark, loc. cit. p. 169. 



The species placed in this genus are for the most part glabrous above and brightly 

 coloured ; the thorax is transversely quadrate, and the posterior tibiae are armed with 

 a double spur ; the claws appendiculate. Too much specific value must not be placed 

 on the comparative length of the joints of the antennae, which I find to differ in the same 

 species according to sex and locality ; they have, however, in most instances, a distinct 

 tendency to gradual incrassation towards the terminal joints. Two species only from 

 Central America were known to Clark. As will be seen I have united here Exarte- 

 matopus with Allochroma ; although both Clark and Von Harold consider these distinct 

 I cannot come to the same conclusion, after the examination of several species. Exar- 

 tematopus has, according to Clark, distinctly incrassate antennae, and, according to Von 

 Harold, the sixth joint greatly thickened and elongate, of which Clark says nothing. 

 This latter character is, however, only peculiar to the male insect, and I have several 

 species before me which prove this assertion. Allochroma sanguineum, Clark, the type 

 of which I have for examination, has exactly the same incrassate antennae, also the 

 same transverse thorax which is said to be peculiar to Exartematopus, but which is 

 found in several degrees of modification in other species of Allochroma. All the 

 species, with very few exceptions of either genus, are glabrous, highly coloured, and 

 generally of the same shape and structure, and it seems to me impossible to draw the 

 line at characters which seem to vary in nearly every species. 



1. Allochroma sexmaculatum. (Tab. XXV. figg. 1-3.) 



Allochroma sexmaculatum, Clark, Cat. Halticidse, p. 185, t. 7. fig. 7 \ 



Hob. Beitish Hondueas, B. Sarstoon (Blancaneaux) ; Guatemala, San Geronimo, 

 Panima, Senahu, and Sabo (Champion) ; Costa Rica (Van Patten) ; Panama (Boucard), 

 Volcan de Chiriqui, David (Champion). — Beazil l . 



Var. a. Elytra with two broad transverse black bands occupying nearly the entire disc, but interrupted by a 



