232 NATURAL ARRANGEMENT OF INSECTS. 



the two preceding; and they are all as well covered with 

 bristles at their articulations,, as those of the terrestrial 

 Geotrupince. There is, in fact, so little difference in 

 degree between the posterior tarsus of O. nasicornis and 

 G. stercorarius, that it is quite obvious they both de- 

 serve to be considered terrestrial scarabs, although se- 

 parated into distinct sub-families by the other parts of 

 their organisation : the claw joint, indeed, of Oryctes is 

 is much more developed ; yet still, although longer, it 

 is not so thick as the first tarsal joint, and, in many of 

 the Brazilian species, it is particularly slender. We 

 may now turn to one of the best known insects among 

 the Megasomince, viz. the Hercules beetle ( M . Her- 

 cules). The hinder tarsi, instead of being shorter, are 

 very considerably longer than the shank; the basal 

 joint, although very slightly thicker, is rather shorter, 

 than the three following, which are all of the same size 

 and length; while the claw joint is so highly developed, 

 that it is equal in length to the three preceding ones : 

 no hairs whatever are upon any of the joints, and the 

 claws themselves are remarkably hooked. Now, it can- 

 not for a moment be doubted that this gigantic insect is 

 completely arboreal, and that its progress upon the ground 

 would be just as slow and unnatural as that of a genuine 

 Scarabceus upon a branch. We have confined the fore- 

 going comparison to the hinder tarsi of these respective 

 insects, not from any supposition that they are more 

 important than the others, but simply because we judge 

 it unnecessary to enter into similar details respecting 

 the remainder : in point of fact, the same relative pro- 

 portions in the joints will be found in all the other legs; 

 premising, however, that the anterior claw joint in this, 

 and nearly all the arboreal Megasomincz, is much more 

 developed, in proportion, than that of the terrestrial 

 Dynastince. 



(205.) From the foregoing observations, it is, there- 

 fore, evident that the Dynastidce comprise two distinct 

 natural groups of equal value, by which the terrestrial 

 and arboreal lamellicorn beetles are united. This opi- 



