332 RHYNCHOPHORA. [ Ceuthorrhynchina. 
they contract the rostrum and limbs beneath their bodies and fall and 
remain motionless; in this condition they are very easily passed over 
as seeds or little pieces of earth or gravel; a few, however, have the 
power of leaping sideways and in this way endeavour to escape; this 
property has especially been noticed in Lhinoncus perpendicularis 
(subfasciatus) and is possessed to a less degree by Rhinoncus Castor and 
bruchoides, Celiodes quadrimaculutus, and Ceuthorrhynchus hirtulus. 
The larve of the tribe do not differ from the ordinary Rhynchophorous 
type ; they are whitish, occasionally yellowish, fleshy grubs; the life 
history of certain of the species is interesting and will be further re- 
ferred to. 
As regards the division of the tribe into genera, there is great 
diversity of opinion ; in the catalogue published in 1888 by the Rev. A, 
Matthews and myself the following were enumerated as distinct, 
Mononychus, Ceeliodes, Ceuthorrhynchus, Ceuthorrhynchidius, Amalus, 
Rhytidosomus, Rhinoncus, Phytobius, Litodactylus, Eubrychius, Tapino- 
tus and Poophagus ; of these Thomson (Skand. Col. x. pp. 194-197) 
includes Rhytidosomus under Ceeliodes (which latter genus he regards 
as distinct), and Ceuthorrhynchidius, Tapinotus and Poophagus under 
Ceuthorrhynchus ; Amalus he considers a separate genus, and the re- 
mainder he places under Rhinoncus ; the genus Mononychus has always 
been regarded as distinct, but this does not occur in the Skandinavian 
fauna. 
Bedel goes considerably further than Thomson and reduees the genera 
which are found in the basin of the Seine, and which are almost 
identical with ours, to three only, Amalus, Mononychus and Ceuthor- 
rhynchus ; of these Mononychus is distinct, Amalus includes Rhinoncus 
and its allies, and Cewthorrhynchus is made up of the species proper, 
and those belonging to the genera Celiodes, Ceuthorrhynchidius, Rhytt- 
dosomus, Tapinotus and Poophagus, and of course to the several sub- 
genera (such as Stenocarus, Megacetes, Cidnorrhinus, &c.), into which 
one or two of these have been divided by Thomson and others. 
M. Bedel, in grouping the species together, makes the following re- 
marks (l.c. p. 162) :—*‘ If we pass in review the series of Mediterranean 
species, we very quickly perceive that the form of the body, the number 
of joints of the funiculus, the dimensions of the rostrum, the develop- 
ment of the pectoral channel, the structure of the femora and of the 
tibia and their terminating brush of hairs (corbei//le) have never the 
value of generic characters ; they are excellent characters for the dis- 
tinction of species, but nothing further;” to a very great extent M. 
Bedel is right, but certain of the characters are in other groups regarded 
as generic and we are brought back to the old question “ What really 
constitutes a genus?” which has never satisfactorily been answered, and 
certainly cannot be answered as far as the Rhynchophora are concerned 
in the present state of our knowledge; as, however, the characters which 
have been given for the various genera belonging to the present tribe 
