396 THE ZOOLOGIST. 



spheres, at first scarcely visible, float freely, and in still water 

 rise to the surface. The embryo hatches about the eighth or 

 tenth day. At first the larval Cod are impelled about helplessly, 

 often the yolk-sac uppermost. These tiny fish have black trans- 

 verse bars, giving them quite a characteristic appearance. In a 

 week's time the yolk-sac is absorbed — the post-larval stage — and 

 the barred pigmentation becomes tesselated or tartan-like. The 

 future back and belly fins are originally continuous membranes. 

 When about three weeks old the head becomes pigmented, while 

 the body assumes more of a greenish yellow hue. Shortly after 

 there is budding of ventral and separation of dorsal fins, and a ten- 

 dency to longitudinal pigmentation of the body. When arrived at 

 about an inch long or over, the fish has assumed quite an adult 

 facies, with barbel and fins complete. From the rock-pools and 

 upper water they descend among the shore algse. By the late 

 autumn they are four or five inches, and by the spring a foot 

 long. A seaward migration then takes place, and in their third 

 or fourth year they return in immense companies as full-grown 

 Cod. 



Sexual maturity, according to Holt, is when the Cod are 

 from twenty-two inches to three feet long, though Mcintosh is 

 inclined to deem twenty inches a fair average. Quite a variety of 

 annelids, crustaceans, and fish form the Cod's diet ; but it is a 

 most voracious, indiscriminate feeder. 



The embryology, post-larval up to the adult stages, of other 

 members of the Cod family have in similar manner received 

 assiduous attention. Besides the movements, the food and the 

 everyday life of the fish themselves in their marine habitat have 

 been carefully watched on all parts of the British coasts, both 

 within (shorewise) and beyond the territorial limits. Thus a mass 

 of evidence and information has accrued, practically instructive 

 alike to fishermen and scientific seekers. 



The young Ling undergoes remarkable transformation in 

 colour and in curtailment of ventral fins, which in the early stage 

 are relatively of enormous length. The eggs of the Torsk and 

 Ling are distinguished by a great oil-globule, which renders them 

 more conspicuous in the water than those of their allies. The 

 Haddock, and to some extent the Whiting, keep to deep water 

 offshore grounds till reaching five or six inches in length, when 



