GENERAL REMARKS ON FISH. 4^ 



continues in his earnest manner: "The dynasty of the Ganoids 

 was at one time co-extensive with every river, lake, and sea ; 

 and endured during the unreckoned eons, which extended 

 from the time of the lower Old Bed Sandstone until those of 

 the Chalk. I may here mention, that as there are orders of 

 plants, such as the Rosacag, and the grasses, that scarce 

 preceded man in their appearance : so there are families of 

 fishes that seem to belong peculiarly to the human period. 

 * * * 4t * rp]^g delicate Salmonidae and Pleuronectidae 

 families to which the Salmon and Turbot belong, were 

 ushered into being as early as the times of the Chalk ; but the 

 Gadidae or Cod Family did not precede man by at least any 

 time appreciable to the geologist." We might follow Miller 

 further in his remarks, and might show the reptilian and 

 ichthyic characteristics in the same animal ; a fish apparently 

 approaching the reptile, and the reptile the fish. 



We do not intend here to go into a lengthy or scientific 

 description of the roe as it exists in the female; its ejection 

 and impregnation by the milt of the male ; its progress in 

 incubation, and the production and growth of the young ; but 

 refer the reader to our article on Pisciculture, for all essential 

 information on so interesting a subject. 



All observing anglers know that the roe is contained in 

 two sacks ; this, as well as the milt of the male, is gradually 

 formed and developed as the fish arrives at the age of 

 puberty, and the same rule of formation, and growth of the 

 roe or milt, is repeated in the same individual after it recu- 

 perates from the exhausting effects of spawning. 



Fish of the genus Salmo, which includes our Brook Trout, 

 are amongst the few that spawn in autumn. The ova of 

 these require water highly aerated, much oxygen being 

 needed in the incubation. These select the gentle current 

 of the streams, but if this is not accessible, as is the case in 



