THE SILURUS GLANIS. 173 
attracting other fish, which mistake them for worms, 
and of serving as feelers.* When the wels perceives 
its prey close enough to be seized, it makes a dart, 
which, considering the width of its gape, and the 
nature of the armature of its mouth, can rarely fail 
to be successful. _ 
To return to our description of the head, we have 
only to mention that the gill-openings are very wide, 
and extend forwards to behind the chin. No other 
European fish has the fins developed in so peculiar a 
manner as the wels ; the dorsal fin is very small and 
short, placed at no great distance from the head, whilst 
the anal fin is very long, composed of about ninety 
rays, and occupies the entire lower surface of the tail, 
running to the caudal fin, with which it is joined ; the 
caudal fin itself is rounded. The pectoral and ventral 
fins are rather small, compared with the size of the 
fish, and the former is provided with a short bony 
spine, which, however, is too feeble to be used as a 
weapon of defence. Tropical species have this spine 
powerfully developed, inflicting with it serious, and 
sometimes fatal, wounds. The structure and arrange- 
* Imuch regret having omitted to make the following experi- 
- ment, which never occurred to me till this moment, and which I 
recommend to those who may have the opportunity of watching a 
wels in an aquarium. I fed my little welses with young breams, 
but I have no doubt that they would take also roe or pieces of raw 
meat. In this case it would be interesting to see whether the wels 
feels the food offered with the barbels before seizing it. 
