THE DYNASTIN^E. 231 



not found in Britain, it appears by no means uncommon 

 in various parts of the Continent. De Geer once dis- 

 covered a considerable number of them, both in the 

 larva and perfect state, in a heap of rich vegetable 

 mould ; and other writers mention its being found in 

 half-rotten tanpits. This is sufficient evidence that 

 this insect feeds upon decayed wood; and it therefore 

 follows,, analogically, that all others, having the same 

 general structure, do the same. The tips of the jaws 

 are rather membranaceous than corneous, and being un- 

 armed with the teeth of the true Dynastince, clearly 

 show that they are employed upon a much softer species 

 of food : in other words, we are brought to the con- 

 viction that the Dynastince in unison with the pre- 

 dominant character of all the other Scarabaida feed 

 upon decayed wood ; and that the Megasomince subsist 

 habitually upon that which is either in a living state, 

 or but just beginning to decay : thus are the two grand 

 and leading characters preserved; and consumers are 

 provided, in these groups, for every stage of vegetable 

 existence, from the flowers, on which alone the Ce- 

 toniance exist, down to the excrement of herbivorous 

 animals, in which the Scarabceince delight to revel. 



(204.) But without looking merely to those cha- 

 racters upon which so much stress has been laid, 

 namely, the internal parts of the mouth, let us see how 

 far the separation here made of the DynastidcB of Mr. 

 MacLeay, into two sub-families, is borne out by the 

 structure of their respective tarsi. We have already 

 seen in what manner the two great divisions of terres- 

 trial and arboreal scarabs are thus naturally charac- 

 terised by their feet ; and this becomes apparent even at 

 the point of their junction. The posterior tarsi of the 

 Oryctes nasicornis may be thus described : they are 

 decidedly shorter than the shank ; almost as slender, in 

 proportion to the thickness of the legs, as those of the 

 GeotrupincB ; the first, or basal joint, is much the largest 

 of the four, the three others being considerably gra- 

 duated; the last, or claw joint, is equal in length to 

 Q 4 



