CHAPTER XII 

 THE COD FAMILY—Continued 



In the previous chapter we have described the habits and brain 

 structure of the fishes, the brains of which are figured in cohimn I 

 of Plate 18, and it may have been noticed, that with these fishes 

 we included the ling, Molva molva or vulgaris, which stands at the 

 top of Column He. Its position there is due to the fact that it is 

 typical of a group of gadidse which have elongate bodies with small 

 scales, and among these we include the blue and Mediterranean 

 lings, and the only fresh-water cod, the burbot or eel-j)out, Lota 

 vulgaris. The Mediterranean ling or molva elongata is much 

 more eel-like than the other lings, and is caught in deep water 

 south-west of the British Isles. It is silvery in colour, but greyish 

 towards the dorsum. The jaws are long and narrow with a pro- 

 truding lower jaw. There are large teeth on the palate arranged 

 in the form of a horseshoe, as we have seen in M. vulgaris, and the 

 teeth of the lower jaw are sharp. The pectoral fin is prolonged into 

 a long filament. There is a barbel on the chin and the first three 

 rays of the ventral fin are elongated. 



According to Hickling, the range in depth of this fish is 220-520 

 fathoms, and as they usually come to the surface with stomachs 

 everted they probably feed in the lower layers. The eyes are large, 

 the diameter of the orbit being approximately one inch. Another 

 interesting feature is the large size of the swim-bladder, which is 

 remarkable for the extent of its rete mirabile ; this in a small 

 specimen measiued four inches in length. When we compare the 

 pattern of the brain of molva elongata with that of the common ling 

 we note that the cerebellum is in both of moderate size and the optic 

 lobes are not large. The acoustic lobes are very much larger in M. 

 elongata than in the common ling, and the somatic-sensory lobes 

 a,re also very large and project beyond the margins of the cerebellum. 

 The prominence of the somatic -sensory lobes is well shown in a 

 lateral view, wliich depicts the cerebellum making a luckle-like curve 

 over these lobes. The facts revealed by this examination, namely, 

 the very prominent acoustico-lateral lobes, similar to those of the 

 hake, and the large somatic-sensory lobes confirm the suggestion 



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