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 - 



* I much 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 



