2 HETEROMERA. 



the series ; the majority of authors appear to have placed it between the 

 series that are, as a rule, pentamerous, and those which are tetramerous 

 or pseudo- tetramerous (the Rhynchophora, Longicornia, and Phytophaga), 

 not, as Dr. Horn remarks, that they have been supposed to have any 

 special relationship to either, nor to be a link between them, but 

 apparently from the fact that in the aggregate the amount of tarsal 

 joints is one less than in the Pentamera and two more than in the Tetra- 

 mera ; others again have proposed to place them at the end of the order 

 as being a sort of synopsis, in general appearance, of the whole ; the best 

 plan, however, appears to be to place them immediately before the 

 Bhynchophora, which certainly appear to be properly placed last; they 

 will then stand as an anomalous group at the end of the ordinary 

 Coleoptera, and through the Pythidae present a decided affinity towards 

 the Curculionidse. 



The larvae are almost as variable as the perfect insects, and in many 

 cases are most curious and extraordinary both in forms and habits ; they 

 will be discussed under the various tribes and genera. 



The series is well represented in Europe by about two hundred genera, 

 which contain a large number of species, the genera Asida, Pimelia, and 

 Mylabris, neither of which are represented in Britain, numbering up- 

 wards of two hundred between them ; fifty-eight genera are found in 

 Britain, but the species are comparatively very few, being only about 

 one hundred and twenty in number; the classification is somewhat 

 difficult from the fact that the characters that seem trustworthy are so 

 liable to exceptions, and in many cases are not very obvious, although 

 the insects to be distinguished are in many cases entirely different in 

 general appearance; Thomson divides the Heteromera as a whole into 

 two divisions, the Globicoxse, which have the anterior coxae globose or 

 ovate, and the Conicoxse, in which they are long, conical, and exserted, 

 and I have, to a certain extent, followed his arrangement ; the genus 

 that I have felt most doubt about is Scraptia, which has been very 

 differently placed by various authors ; it seems, however, to be most 

 closely allied to the Mordellidae, and I have therefore placed it as a 

 separate family near that group, rather than with the Pedilidae, which are 

 more closely allied to the Anthicidse : in point of fact I have not 

 adopted the family Pedilidae at all, as Xylopliilus, including EugUnes, 

 appears to be better placed either with the Anthicidse or in a separate 

 family, and if we exclude this genus and Scraptia, we have no further 

 British representatives of the family. 



I. Anterior coxal cavities closed behind, 

 i. Tarsal claws simple. 



1. Anterior coxae globose, rarely oval, not prominent ; pen- 

 ultimate joint of tarsi very rarely bilobed and spongy 



beneath TENHBRlONiD.fi. 



2. Anterior coxae conical-ovate, prominent, penultimate 

 joint of tarsi bilobed and spc ngy beneath 



