136 



MANDIBULATA. — COLEOPTERA. 



incrassated : head rounded anteriorly : body more or less hemispheric : thorax 

 transverse : legs formed for walking : tibiae compressed, spinose, with spurs at 

 the apex : — tarsi five-jointed, filiform, the basal and terminal joints elongated, 

 the latter with two unequal claws. 



The passage from the last family to the present is doubtless most 

 natural, and the habits of the insects are not widely dissimilar ; the 

 Hydrobii subsisting in a great measure upon decaying vegetable 

 matter, and the Sphseridiidse upon putrescent matter of a similar 

 nature, that has previously passed through the bodies of animals. 

 Again, many of the species of Cercyon are found only in damp 

 places that are inundated in the winter, while others affect places 

 of greater aridity. Their larvae are unknown. 



This family embraces two very distinct genera; which were 

 divided by Dr. Leach ; and may be known by the following succinct 

 characters. 



r solida : elytra striata : 105. Cercyon. 



Antennarum clava 



i souaa 

 I laxe i 



imbricata: elytra striis immunia : . 106. SphjERIdium. 



Genus CV. — Cercyon, Leach. 



Maxillary palpi four-jointed, the basal joint minute, the following elongated, 

 slender at the base and greatly incrassated at the apex, the third nearly as 

 long, slender, the terminal much shorter, rather stouter, ovate, attenuated at 

 the apex. Antennae very slender at the base, the four terminal joints forming 

 an abrupt compact imbricated club : body very convex : thorax short, trans- 

 verse : scutellum abbreviated : wings ample : elytra entire, striated, acute at 

 the apex : legs moderate : tibia compressed, setose exteriorly ; tarsi short, 

 the anterior simple in both sexes. 



The globose form and comparative minuteness of the insects of 

 this genus well discriminate them from the Sphseridia, from which 

 they were separated by Dr. Leach : they are unquestionably very 

 closely allied to the Hydrobii : their pabulum chiefly consists of 

 horse-dung; and they are most abundant during the early summer 

 months. The species have been greatly neglected ; but from a 

 careful examination of the original Marshamian specimens, as well 

 as of a vast number obtained by myself from various sources, I 

 cannot but consider those recorded in the following pages as distinct, 

 with the exception of such as are given with doubt *. The genus 



* I may here take occasion to remark, that the new species in this genus, as 

 well as in most other instances, are rarely introduced upon the examination of 



