404 ME. r. DAT OIv' BEITISH SALMONES. 



subsequently as those of the salmou. AnyhoAV, auy trout-oya 

 received came from Mr. Eraucis Francis, who obtained them from 

 an affluent of the Thames. On July 3rd, 1866, the first pair of 

 trout matured in Tasmania had the ova and milt taken from 

 them. "The ova shipped to Tasmania consisted of three* 

 batches of eggs, supplied through the kind offices of Mr. Erank 

 Buckland and Mr. Francis Francis," and were obtained from the 

 localities alluded to. Mr. Arthur t informs us that the first 

 successful trout-hatching in Otago occurred in October 1868, 

 from 800 ova obtained from the natural spawning-beds of S.fario 

 in Tasmania ; these and a second lot the subsequent year formed 

 the whole of their original stock, some of which were first liberated 

 in the streams in November 1869. 



As these New-Zealand fish are clearly descendants from our 

 brook-trout {S.fario), it is evident that they might be expected 

 to correspond in structural characters with their ancestral stock. 

 But results show that they have not done so. Without entering 

 minutely into Mr. Arthur's interesting paper, which should be 

 studied in the ' Transactions ' of the Society in which it was 

 published, I will restrict myself to his conclusions. Scotch trout, 

 according to Stoddart, show a yearly increase of about one third 

 of a pound in weight ; while in Otago they grow so rapidly and are 

 so fat that they have reached an average yearly increment of 

 from 1 lb. to 2 1 lb. Already the various streams have stamped 

 the trout with local peculiarities : in some they are plump 

 almost to deformity ; their proportions are not constant, neither 

 are their colours ; while examples are said to have been seen up 

 to 20 lb. in weight. What is of extreme interest, however, is, as 

 already remarked, that these fat fast-growing fish have not the 

 number of cfecal appendages of their ancestors, but with increased 

 necessities, due to a superabundant supply of food, they have 

 augmented m number — not varying between 33 and 47, the 

 extreme limits Dr. Giinther assigns to the Salmo fario, but 

 from 43 to 54; while among the entire six British species he 

 described (Loch-Leven trout not included) he limited these 

 appendages to between 33 and 50. Thus the brook-trout, 

 transported to a climate where food is abundant, has taken on 

 structural changes affording a most conclusive proof that the 



* Buckland says he believes Mr. Francis Francis sent some trout-eggs 

 obtained from Hungerford at the same time as his were forwarded. 

 t Transactions of the Otago Institute, July 9th, 1878. 



