74 PHYTOPHAGA. 



as Brazil. Their determination is, except in the case of peculiarly-coloured species, 

 often a very laborious and difficult task, inasmuch as a certain system in regard 

 to the elytral and thoracic prominences prevails to a more or less extent in most of the 

 species, which the clearest description cannot always make plain. A great many 

 undescribed species are yet contained in collections. The group has been divided into 

 eight genera. 



DIASPIS. 



Diaspis, Lacordaire, Mon. p. 646 (1848). 



This genus was founded by Lacordaire to include certain species with two distinct 

 scutella, the only instance in which this peculiarity is to be found in the whole of the 

 Coleoptera. At present two species have been described as belonging to this genus, 

 one by Lacordaire, the other by Mr. Baly ; one or two more species, which are contained 

 in the collection of the last-named author, must also be classified with these, as they 

 show two scutella. I must confess, however, that my belief in the stability of the 

 characteristic peculiarity of this genus is somewhat shaken, as I have now before me 

 three specimens of the same species (Chlamys memnonia), one of them Lacordaire's 

 type, which shows two scutella and was consequently put by Mr. Baly in the genus 

 Diaspis; two other specimens, however, from Mexico and Guatemala respectively, 

 which agree in every thing else with the type, have but one scutellum, and no sign 

 whatever is visible of a second one ; I therefore think it not improbable that the 

 visible presence of a second scutellum is due to the imperfect closing of that part of 

 the elytra. In D. paradoxa (the type) the fissure is much greater, and consequently 

 the scutellum larger than in any other species which I have seen, where the second 

 scutellum is very narrow and even almost obsolete ; so that, in the case of Lacordaire's 

 Chlamys moestifica and C. memnonia, the presence of a second scutellum seems to 

 have escaped this celebrated author's observation. As to the second characteristic, 

 the bifid claw, which is present in D. paradoxa, is certainly absent in I). memnonia. 

 More material, however, is needed to form a conclusive opinion. 



l. Diaspis paradoxa. (Tab. V. fig. 2.) 



Diaspis paradoxa, Lacord. Mon. p. 646 \ 



Hob. Mexico, Cordova (Salle), Tabasco K 



The specimen from M. Salle's collection has the elytral sculpturing less strongly 

 marked than one from Yucatan in the collection of Mr. Baly (which is a female) and 

 the type mentioned by Lacordaire and described as a variety sent to him by Pilate. 

 M. Salle's specimen is a male, and has the posterior thighs protruding beyond the 

 abdomen. 



The second scutellum is also plainly visible in this specimen, which is the second I 



