Genera of the Cossonidoi. 431 
mides and Mecopus ; and although the breast Is not chan- 
nelled for the reception of the rostrum, some of the species 
ncA^ertheless have a faint tendency for the slight pectoral 
cavity which is very appreciable in Sphadasmus, 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 
Avith which its intermediate tibiffi 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 Avhich it may be worth Avhile to draAV 
attention. Thus, the only groups, outside the anomalous 
subfamilies Notiomimetides and Onycholipides, in Avhich 
the tibial hook (that almost universal appendage) is 
obsolete, are Thaumastophasis, Aorus, Lipancylus, and 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 Ave might perhaps add Amorpho- 
cerus to the number, Avere it not that the tibije in that 
genus are eminently spinose at their apex ; and it may be 
a question hoAv far the largest of the terminal spines, 
although 7iot proceeding from the outer angle, represents 
the tibial uncus. Another feature Avhich might be noted, 
and which certainly is not in accordance Avith 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 
xohich are beyond a question, in Avhich it is, so far as I am 
aware, indicated, is Odontomesites ; and even there the 
tooth is but obtixse and anguliform, and exists only in the 
male sex. It is however more strongly expressed in Notio- 
mimetes, Coptorhamphus and Homaloxenus, — all of Avliich, 
nevertheless, are, in other respects likcAvise, 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 hoAvever (albeit 
subject to complete obliteration) in Lamprochrus and 
