THE DYNASTINiE. 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 Scarabceidce — 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- 

 toniancB 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 

 Geotrupince; 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 



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