COLEOl'TERA. — NECROl'II AGA. 133 



even still more distinct, as may be observed in the genera Necro- 

 phorus and the larger Staphylinida;, as well as in the genus Micro- 

 peplus, belonging to the Nitidulidge. 



The families into which Latreille divided this group in his 

 "Genera," were — 1. Silphales ; 2. Nitidularias (divided into the Pel- 

 tides, Nitidulariae propriae, and Ipsides) ; 3. Scaphidiles ; and 4. Der- 

 mestini. In his later works, however, he has adopted Dumeril's views, 

 and united them, together with the Histeridas, Byrrhidae, and the 

 aberrant Philhydrida, into a group called Clavicorncs. In all his 

 works, however, he placed many of the small species far apart in a 

 group, which he termed Xylo[)haga. Mr. MacLeay divides the stirps 

 into the four following families : — 



Normal Group ? 



Club of antenna' elongate, perfoliate, 4 or .'j-jointed. j" Scaplildic].x\ 



(Silplia Linn.) (^ Silphiche. 



Aberrant Group ? f XitidulicL-e. 



Club of antenna; short, 2 or ;3-jointed. -; Engida>. 



(Uermestcs Linn.) (_ Dermestida;. 



These families correspond with those given by Latreille in his late 

 works, with the exception of the Engidae, in which Mr. MacLeay 

 introduces a great number of insects which Latreille, too much 

 influenced by a desire to retain the tarsal system, had placed among 

 the Tetramerous Xylophaga: although, as I have endeavoured to prove 

 in the LinncEcin Transactions (vol. xvi.), this is evidently a family, 

 or rather perhaps a series of allied families, characterised by the 

 variation in the structure of the tarsi. 



Of the affinities connecting these various families too little is yet 

 known, either of their anatomical characters or the structure of their 

 larvffi, to enable us to speak with precision upon the subject ; in like 

 manner, the views of Geoffroy, Linnaeus, and other early authors, who 

 never dissected a single insect, cannot be considered as entitled to 

 that weight, with reference to the juxtaposition of these families, 

 which Mr. MacLeay seems disposed to give to them. 



The following observations, however, by Mr. Kirby are worthy of 

 attention : " Though the transition from the Brachclytra by Nccro- 

 phorus to the Necrophaga, especially the Silphida^, is so evident, yet 

 the road to be taken when we depart from the latter tribe is not 

 equally clear. The Nitidulida;, indeed, manifest a close affinity to the 

 Silphidaj ; but the Engidai seem separated from both by a rather 

 wide interval, and from them various routes present themselves. 



K 3 



