MR. CURTIS ON HYPOCEPHALUS, A GENUS OF COLEOPTERA. 233 



pliant, are evidently for grinding or mastication, the jaws by themselves being useless in 

 that respect, yet I expect they are capable of lateral motion. 



Having shown that this pentamerous beetle agrees with the Lamellicomes in various 

 ways, whilst it disagrees with the Longicornes in many, I will assign my reasons for asso- 

 ciating Hypocephalus with the former Family, even were the claims balanced, excepting 

 the tarsi. 



I confess that I have still so good an opinion of the tarsal system of Geoffroy, and 

 adopted by Latreille, as a basis for the primary divisions of the Coleoptera, that I do not 

 hesitate to challenge any systematist to exhibit another, better, more useful, or less 

 objectionable*. It is usual to term this an artificial System, but that which is based upon 

 anatomy is no more artificial in Entomology than in any other Class of animals, and the 

 skeletons of Insects being external, the joints of the legs and feet are as purely anatomical 

 as the bones (the femur, tibiae, &c.) of any quadruped or bird. In pursuing the tarsal 

 system, no one will attempt to deny meeting with many exceptions to the general type of 

 form, but these occur in the minuter groups, which often seem to become feeble in their 

 development, and depart from the perfection, if I may so term it, exhibited by the large 

 and typical species. In the Family Staphylinidce, for example, the number of joints 

 varies in the feet, but this is confined to the minute species f, and to an amount so small, 

 that it cannot justify our abandoning so valuable and tangible a character for dividing 

 the enormous Order Coleoptera. And when we examine the large and perfectly-deve- 

 loped examples, which must decide the position of a Family, we find the Staphylinidce an 

 undoubted pentamerous group % ; the larvse also in this instance assimilating so well 

 with those of the Carabidce, that it is at present difficult to decide to which family they 

 belong. 



My experience teaches me, that as regards affinities, animals do not descend in their 

 claims of relationship, viz. If the types of a group exhibit certain perfections in their 

 structure, that group has no absolute affinity to a family typically less perfect, and cannot 

 therefore be transferred to that inferior group, without doing a violence to nature's laws. 

 For instance, it would be unnatural to remove a member of the Family Carabidce, with 

 its 6 palpi, to any other less perfect, however modified the tarsi might be, or however 

 strange its contour §. On the same principle, its pentamerous character excludes it from 

 entering the lines of the Heteromera, or any other of the great sections. 



This is my reason for maintaining that Hypocephalus cannot be admitted amongst the 

 Longicornes : it must find a place amongst the Pentamera. It may be affirmed that the 

 Tetramera are pentamerous, — this I cannot admit ; the portion considered as a 4th or extra 

 joint, even when articulated, is not the analogue of the 4th joint in the Pentamera ; it is 



* Consult Latreille' s Genera Crustaceorum et Insectorum, and that admirable volume, the Considerations Generates. 



t Vide Curtis's Brit. Ent. Homalota, pi. 514 ; Falagria, pi. 462; Bledius, pi. 143. 



% See the dissections in the Brit. Ent. of Emus hirtus, pi. 534, and of 1 7 other genera of the same family, all of 

 which are pentamerous ; and it is deserving of remark, that generally when the number of joints is reduced, they fail 

 in the anterior feet : vide Phytosus, pi. 718. 



§ Were it not for the number of the palpi, who could imagine that Mormolyce and Omophron were types of the 

 same family — and that Carabidce ? 



VOL. XXI. 2 I 



