It is not easy to determine correctly the systematic position of the Cory- 

 lopJiidfB ; from the peculiar formation of the anteuna3, from their position when at 

 rest, and from the large, elongate, and free or iirominent anterior coxse, and also 

 from the general arrangement of the skeleton of the under side, it is impossible to 

 ignore their close afiSnity to the Silphida. And for these reasons I believe that to 

 place the Corylophida before the Silphidce would be the most natural arrangement 

 that could be made. In external appearance many genera of this family present a 

 resemblance to the Anisotomhue so striking, that it is difficult at first sight to 

 determine whether they do not really belong to the Sllph'uhe. In Pdtinus and 

 some others the prosternum is reduced, as in Agathidium, to the smallest possible 

 dimensions, and leaves the coxal cavities open in front and behind. If, therefore, 

 the Corylophidce are placed before the Silphidce in proximity to the Anisotomince, a 

 much greater harmony of form and anatomy would be attained than by leaving 

 them where they now stand, or by removing them to any other position. 



In the foi-egoing remarks I refer to the true Corylophidce alone ; those species 

 which I have separated into a distinct family, the Pseudocorylophidce, I would 

 retain in the position now occupied by the whole family — I mean in the vicinity of 

 the Coccinellidce. 



The Pluenocephalidce make a yet further approach towards the Silphidce by 

 their bilobed maxillae, and by the contiguity of their posterior coxte, which are very 

 widely separated in all the Corylophidce. Like many Silphidce, the posterior coxa 

 of Phcenocephalus are also furnished with prominent trochantins, a structure never 

 found in the true Corylophidce. It may be thought unadvisable to create a separate 

 family for the reception of a single species, at present represented by a single 

 specimen. But I do not see any other course to pursue. The bilobed maxillse and 

 Silphide posterior coxsb are anatomical characters of too much importance to 

 permit the association of Phcenocepludus with the Corylophidce, and it is still farther 

 removed from the Pseudocorylophidce by every part of its anatomy. Since, then, 

 the very same characters which remove Phcenocephalus from the Corylophidce 

 indicate its affinity to the Silphidce, I feel that I am justified in placing Phceno- 

 cephalus as a connecting family between the true Corylophidce and the Silphidce. 



By the above arrangement the Families would stand in the following order, 



viz. : — 



Leptinid.e. 



cokylophid.e. 



Ph^enocephalid^. 



Silphide. 



And thus a greater harmony of both form and anatomy would be effected than is 

 jDresented by any existing systematic arrangement. 



In this work, as well as in others, I have often described the anterior coxal 

 cavities as "open in front and behind." Some entomologists, I find, object to the use 

 of that term, but I do not think that any other definition could express so accurately 

 the form of the part in question. It would be manifestly absurd to describe a cavity 



