COLEOi'TEKA. AGATIIIDIXD.T;. 131 



tarsal joints is apparent, and ought not therefore to be relied upon as 

 affording clear grounds of relationship with other groups, cannot be 

 denied ; and accordingly Fabricius placed such of these insects as he 

 was acquainted with between the Sphaeridiidie and Byrrhida?, whilst 

 Mr. Stephens has placed them at the end of the Philhydrida. I can, 

 however, by no means persuade myself that it would not be more 

 natural to introduce this family amongst the Necrophaga ; indeed a 

 comparison of Mr. Curtis's dissections of Leiodes and Catops, or mine 

 of Agathidium and Choleva,will sufficiently prove this. The relationship 

 of some of the genera, inter se, requires investigation, which, from 

 the exceeding minuteness of some of them, is very difficult. 



These insects ai*e of a small size, of a rounded or oval form, gene- 

 rally convex, and occasionally contractile into a ball (^Jig. 9. 8. Aga- 

 thidium atrum) ; the antennae are short and elavate, the club varying 

 in the number of its joints {^fig. 9. 13. antenna of Agathidium). In 

 Leiodes {Jig. 9. ic. L. cinnamomea, the truffle-beetle $ ), which has 

 the tarsi heteromerous, the club of the antennae consists of the five 

 terminal joints, the second of which is very small i^fig. 9. 17. the 7th, 

 8th, and 9th joints of the antenna of Leiodes). In Agathidium, which 

 is also heteromerous (^fig. 9. 14. the anterior, and 9. 1.5. the posterior 

 tarsi), the same occurs, but less stronglj^ marked {fig- 9. 13.); 

 and this peculiarity is again found in the Pentamerous Cholevidae 

 {.fig- 9' 23.), whicii indeed Mr. Curtis appears to consider as probably 

 entering the same family. Until, however, these groups have been 

 rigidly investigated, and their structure ascertained, as well as an 

 acquaintance with their larvae obtained (of which we are still ignorant), 

 it is impossible to decide upon the affinities of these insects. The palpi 

 are generally short and filiform, the maxillary being terminated by 

 an acuminated joint {fig. 9. il. maxilla, j'^/. 9. 12. labium, of Agathi- 

 dium atrum). The labrum is transverse {fig. 9. 9.), and the mandibles 

 nearly triangular, without teeth [fig. 9. lo.) ; the legs short, and some- 

 times spined. The species are generally found in damp situations, 

 inhabiting putrescent vegetable matter ; some of them frequent flowers, 

 and many may be often taken upon the wing in the hot sunshine. 



The British genera introduced into this family by Mr. Stephens are 

 described in the Generic Synopsis, with the exception of Tritoma ; 

 which, as Latreille long ago observed, belongs to the Erotylidie, but 

 which Mr. Curtis has formed into a distinct family, named Tritomidiu. 

 The species of Leiodes are amongst the largest British insects in the 



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