Genera of the Cossonidcc. 431 



mides and Mecopus ; and although the breast is not chan- 

 nelled for the reception of the rostrum, some of the species 

 nevertheless have a faint tendency for the slight pectoral 

 cavity which is very appreciable in Spho.dasmus, Mecopus, 

 &c., and which implies at all events an exceedingly different 

 situation, in a natural system, to that which is occupied 

 by the Cossonids. Moreover, the large and robust spine 

 with which its intermediate tibias are furnished towards 

 their external apex is quite without precedent in the present 

 family, and I have had no hesitation therefore in expunging 

 the genus from our list. 



Glancing at the 122 genera embodied in this paper 

 (75 of which have been treated as new), there are one 

 or two points to which it may be worth while to draw 

 attention. Thus, the only groups, outside the anomalous 

 subfamilies Notiomimetides and Onycholipides, in which 

 the tibial hook (that almost universal appendage) is 

 obsolete, are Thaumastophasis , Aorus, Lipancylus, and 

 Xenocnema (though in Homaloxenus it is greatly reduced 

 in dimensions). And we might perhaps add Amorpho- 

 cerus to the number, were it not that the tibiae in that 

 genus are eminently spinose at their apex ; and it may be 

 a question how far the largest of the terminal spines, 

 although not proceeding from the outer angle, represents 

 the tibial uncus. Another feature which might be noted, 

 and which certainly is not in accordance with what I had 

 originally imagined, is the excessive rarity of anything 

 approaching to a dentate structure of the femora. The 

 only group indeed, the truly Cossonideous affinities of 

 which are beyond a question, in which it is, so far as I am 

 aware, indicated, is Odontomesites ; and even there the 

 tooth is but obtuse and anguliform, and exists only in the 

 male sex. It is however more strongly expressed in Notio~ 

 mimetes, Coptorhamphus and Homaloxenus, -all of which, 

 nevertheless, are, in other respects likewise, abnormal, 

 their right of location in the present family being possibly 

 open to dispute. The third peculiarity, concerning which 

 I would say a few words, is more superficial, and yet, as a 

 mere aid in the identification, it is practically of consider- 

 able importance : I refer to the extreme scarcity of metallic 

 tints which is observable amongst the Cossonids. A 

 brassy lustre, sometimes merging into green, is almost the 

 only one of which I am cognizant, and even that is re- 

 markably uncommon. It is conspicuous however (albeit 

 subject to complete obliteration) in Lamprochrus and 



