60RTATION. 35 



First dorsal of 6 spines 



Anal spineless ; ventrals with a spine and 5 rays Gobius 

 (pictus). 



First dorsal of 6 to 10 spines 



Anal spineless ; ventrals with or without a spine and with 

 less than 5 rays Cottus. 



First dorsal of 6 or 7 spines 

 Anal with i spine Gobius. 



First dorsal of 8 or 9 spines 

 Anal with 3 spines Labrax. 



First dorsal of 14 or 15 spines 

 Anal with 2 spines Perca. 



In only one British fish with one dorsal fin are there no ventrals, 

 and that is the wolf-fish or cat-fish (Anavrhichas lupus), whose 

 powerful teeth and general ugliness 

 have become proverbial (Fig. 18). 

 In only two genera are the ven- 

 trals rudimentary, and in each 

 case they surround a sucker. One 

 of them is Lepadogaster, which we 

 sorted out before so far as L. 

 gouanii was concerned, owing to 

 the vertical fins being continuous ; 

 in the two remaining species, the 

 suckers (L. decandollii and L. 

 bimaculatus) the vertical fins are not 

 continuous, the last species being 

 distinguished from the others by 

 having a black ocellated spot under 

 the tip of the pectoral. In all 

 the species there are less than 20 

 rays in the dorsal. In Liparls 

 the dorsal rays exceed 20 in number ; the sea-snail, L. vulgaris, 

 about six inches long, is streaked on the body, Montagu's sucker, 

 L. montagui, which is about half the length, is spotted on the body. 



This clears us of the cripples, and leaves us only with such 

 fishes as have the dorsal and ventrals properly developed. In four 

 genera the ventrals are jugular, these comprising the rocklings, the 

 blennies, and the torsk. The rocklings (Motella) have the fore part 

 of the dorsal in the shape of a fringe with a long ray to begin with. 

 The three common species are known by their barbules the five- 

 bearded, four-bearded, and three-bearded and the rare species, 

 M. macrophthalma, by its unspotted body, distinguishing it from the 

 three-bearded rockling, which, like it, has three barbules, but, unlike 

 it, has a large number of spots and blotches on its upper parts. 



The blennies have the dorsal low in the middle and small 

 ventrals. One, the butterfly blenny (Bhnnius ocellaris), differs from 

 the others in having an ocellated spot on the first dorsal. Another, 

 the shanny (B. pholis), has no tentacle over the eye ; another (B. 



Fig. 18. TEETH OF CAT-FISH. 



