amined, seems obsolete. I have found G. Hentzii in Milton, 

 with the spots obsolete in the same way. Can yours be a 

 small individual of that species ? The specimen received in 

 the letter is obviously distinct from the other ; the thorax 

 not only being much the widest behind, but the posterior 

 tubercle rounded or top-shaped. This being the case, I 

 am still ignorant of the appearance of the mentum, and will 

 be greatly obliged to you to inform me whether the gular 

 emargination is deep or shallow, and to note any other particu- 

 lars in which in that part it may differ from its congeners. I 

 am suspicious that this insect will prove to be the C. variolosus 

 of Kirby, in which the notch of the back part of the mentum is 

 very small, as in C. Sayi, and does not extend down to the 

 bottom, as in 0. castanem?^ C. Hentzii^ and your specimen. 

 This can be ascertained without dissection. 



HARRIS TO HENTZ. 



MiLTOX, Nov. 3, 1827. 



It is an undoubted fact that in generalizing the characters 

 of great divisions, as M. Latreille does, many insects allied by 

 natural affinities must be included, which, in some one or 

 two particulars, may form exceptions to the general defini- 

 tions. That this may be the case in regard to the Phen- 

 godcs I think is highly probable, as it is in that of other 

 genera ; but these exceptions, though embarrassing to the 

 student, are of no consequence in a philosophical view. You 

 may have observed that the Pselaphi are dimerous, yet are 

 they most correctly arranged by Leach (in Samouelle's Com- 

 pendium) and by MacLeay in the family of Staphylinidce, to 

 which they are obviously related by natural affinities. On the 

 contrary, Parandra and some of the Cucujidce are really 



OCCAS. PAPERS B. S. N. II. — 1. 3 



