MONOPLATUS. 453 



further distinguished by the more or less filiform palpi, although in that respect 

 instances are not wanting in which intermediate degrees in the shape of these organs 

 make their classification, according to Clark's monograph, very doubtful. 



Amongst the eighteen species described by Clark from Tropical America none were 

 known to him from our region, from whence we now add two species. 



1. Monoplatus Mvus. 



Monoplatus fulvus, Baly, Trans. Ent. Soc. 1879, p. 254 l . 



Hab. Mexico, Ciudad in Durango (Forrer) ; Guatemala, Cerro Zunil (Champion) ; 

 Panama, Volcan de Chiriqui (Champion).— Peru, Chanehamayo l . 



I have carefully compared the type of M. fulvus (contained in the Baly collection) 

 with the specimens obtained at the above localities, and find our insect to be un- 

 doubtedly identical with that species. M. fulvus is evidently a species subject to con- 

 siderable variation, some specimens being at least one half larger than others ; in a 

 few examples the suture shows an elongate triangular piceous spot or narrow band near 

 the base. The single specimen from Mexico has the thorax much more closely and 

 evenly punctured, but I cannot find any other marks of distinction. M. fulvus may be 

 known from its allies by its depressed upper surface, the want of any depressions 

 between the eyes, the punctured head and thorax, and the sinuate transverse groove of 

 the latter ; and also by the distinctly toothed posterior tibiae, a character much more 

 plainly visible than in many other species of the genus I have examined. Some 

 specimens agree absolutely with the type, and intermediate degrees are not wanting. 



2. Monoplatus quadraticollis. 



Entirely fulvous, glabrous; head nearly impunctate; thorax subquadrate, extremely finely punctured, with 

 a transverse groove near the base ; elytra closely and distinctly punctate-striate, the base with an obscure 

 greenish-seneous spot. 



Length 1^ line. 



Head. rather broader than long; the vertex with a few extremely minute punctures; the frontal tubercles 

 scarcely raised ; antenna rather more than half the length of the body, the second and third joints small and 

 of nearly equal length, the following joints elongate ; thorax subquadrate, all the margins straight, the 

 surface elosely and extremely finely punctured, the basal groove distinct and placed close to the margin ; 

 elytra with the basal portion very slightly raised and of a metallic greenish ameous colour, the rest of the 

 surface pale fulvous, closely and distinctly punctate-striate, the punctuation diminishing, however, in 

 depth towards the apices ; posterior femora rather elongate, extending slightly beyond the elytra. 



Hab. Guatemala, San Geronimo (Champion). A single specimen. 



The nearly impunctate head and the finely punctured and subquadrate thorax well 

 distinguish M. quadraticollis from M. fulvus, to which in its general coloration it is 

 closely allied. It is probable that the amount of the metallic greenish colour of the 

 elytra is subject to variation. 



