Genera of the Cossonidce. 507 
allied forms wliicli I regard as Tetratemni. In Dryoph- 
thorus proper, however, the anterior coxje are rather more 
approximated than in Tetratemnus, the body is more 
elliptic (or medially-widened), the prothorax is a trifle less 
developed, the elytra are not so broadly cariniform at their 
apex, and the rostrum, antennge, and legs are appreciably 
longer. Nevertheless in their opake and very coarsely- 
sculptm*ed surface (which is more or less densely besmeared 
with whitish-brown, mud-like scales), as well as in their 
costate elytra and 4-jointed funiculus, and in the fact of the 
fourth articulation of their slender, filiform feet being (in- 
stead of minute and hidden) exposed and distinct, the two 
genera are coincident. The D. li/mexylon, which (as just 
stated) may perhaps prove to be the only Dryophthorus 
proper hitherto made known, appears to occur, more or 
less sparingly, throughout northern and central Europe. 
5. Tetratemnus ( WoUaston, Trails. Ent. Soc. Lond. 9. 
1873). — As already implied, the members of this genus, 
which (if my conclusions be correct) are ea-^ra-European 
and appear to be widely spread over the world, present 
many characters which, as it seems to me, cannot but 
distinguish them generically from the European Dryoph- 
thorus lymexylon. Not to speak however of those species 
which I have had no opportunity of examining, and which 
may or may not prove to be Tetratemni, I may add that 
at any rate the Japanese Cossonid (the T. sculpturatus, 
Woll.) for which the group was proposed, recedes from the 
D. lymexylon in its anterior coxa3 being rather more 
widely separated, whilst the hinder pair, on the contrary, 
are not quite so remote as in that insect ; in its antennje, 
rostrum, and legs being a little shorter ; in its prothorax 
being proportionately a trifle more developed ; in its elytra 
being narrower and more parallel (or laterally-compressed) 
and very much more broadly cariniform on either side of 
their apex ; and in its tarsi being especially more abbre- 
viated. Its rostrum also is less appreciably widened 
immediately in front of the particular point at which the 
antennre are inserted. Its dark and opake surface how- 
ever is as coarsely sculptured, and besmeared with the 
same kind of whitish-brown, mud-like scales (or, as it 
were, scaly deposit), as in Dryophthorus proper. Although 
it is probable that the group has a wide geographical 
range, the T. sculpturatus is, (for the reason already 
TRANS. ENT. SOC. 1873. — PART IV. (OCT.) O O 
