10 i 



MOTELLA. 



The definiLion of tliis genus bj' Cuvier is, the anterior dorsal fin 

 so low as to bi3 scarcely perceptible', which, standing alone, is at least 

 as applicable to the ver}' different genus Rmiiceps as to this. But tlie 

 organ often represented as the first dorsal Hn, in this genus has no 

 nearer title to the name of a fin than what arises fVom its situation 

 at the anterior portion of the back, where its seat is in a chink, 

 from whence it projects when the fish is in the water, but it lies 

 almost liidden when the fish is dead. It does not possess rays, as do 

 all the true fins of these fishes; but it is formed of membrane, Irom 

 the edge of which rises a thickly placed row of threads, the foremost 

 of which is the stoutest and most prominent. When these fishes are 

 alive in their native element, and resting, as they familiarly do, on 

 the ground, with all their true fins at rest, this organ is in continued 

 and rapid action; and its intimate structure shews that while it is 

 destitute of any power of propulsion, or of regulating motion, it is 

 well furnished with nerves which render it acutely sensible to impressions. 

 This dorsal membrane is in fact supplied with a special nerve, which 

 reaches it directly from the brain, and which also passes onward to 

 the true dorsal fin. A branch of this nerve also goes to the pectoral 

 and ventral fins, which are thus endued with particular powers of 

 sensation, in addition to those of action, the last-named faculty being 

 influenced into energy by branches of the intercostal nerves. The 

 lUcial nerve also divides into four branches, one ol which passes to 

 the back of the head and upper portion of the outside ot the orb t; 

 a second branch passes through the lower portion of the orbit, and 

 also supplies the director muscles of the eye itself, whilst the other 

 two are distributed to what may be spoken o'"' as the face. These 

 observations have been obtained from examination of the rhree-bearded 

 Ilockling, 2Iotella vuhjaris or tricirrata, but it is probable that they are 

 equally applicable to the other species of this tamily; and they tend 

 to shew the exquisite provision which is made for the supply oi organic 

 sensibility to a family of small fishes, the lives oi which are for the 

 most part passed in places where feeling is more important even than 

 si'^ht, as well for their safety as subsistence. The essential character 

 of the genus Motella is, that with the othoi portions of structure of 

 the gadoid family, they possess barbs on the upper and lower jaws, 

 together with a ciliated membrane, which is sealed in a chink between 

 the head and doisul tin. 



