Bibliographical Notices. 289 



family before examining the witnesses. The difficulty of investigating 

 the subject is we acknowledge great, and when we know that it has 

 been undergoing strict research by persons well qualified for the task 

 for several years without complete information being obtained, we feel 

 even more anxious to understand the mystery which involves the " lives 

 and loves" of these very valuable inhabitants of our rivers and oceans. 

 Mr. Yarrell, Sir W. Jardine, Dr. Parnell, and Mr. Shaw of Drumlanrig 

 are all either now, or have been very lately working on this subject, 

 and the fruits of their researches will eventually leave little to be accom- 

 plished. Sir Francis Mackenzie of Garloch is about to form extensive 

 stews for the breeding of salmon, and to re-perform some of Mr. Shaw's 

 experiments. The experiments of the latter observer detailed to the 

 Royal Society of Edinburgh, and published in Professor Jameson's 

 Journal, are of the greatest importance ; they have been conducted with 

 great care, and so far as they have been prosecuted have been accom- 

 panied by results as satisfactory perhaps as we could expect from the 

 whole difficulty of the subject. The sum of our knowledge at the 

 present time, so far as regards the common Salmon, is, that we have 

 hitherto been in error in considering its growth to be rapid during the first 

 stages of its existence, and that it does not migrate until at least one 

 year's residence in the fresh waters. On reaching the sea however the 

 increase in size becomes very great, exceeding one pound in weight 

 monthly. It has been further proved incontestably we think by Mr. 

 Shaw, that the great proportion of the small fish called Parrs, or hi the 

 English rivers Pinks*, are the first state of the young Salmon previous 

 to its assuming the migratory dress ; but the additional proposition that 

 the Parr does not exist at all as a distinct fish, is extremely question- 

 able, and still requires investigation. At present the opinions of all 

 our best ichthyologists are in favour of its distinctness, and the minute 

 and careful differences detailed by Dr. Parnell in his " Fishes of the 

 Frith of Forth," go very far to prove every thing that is wanting. The 

 history of the other migratory fish remains nearly in the same state in 

 which it has been for the last thirty years, though the works before us 

 have commenced their elucidation, and some experiments are now in 

 progress. The geographical distribution of the species has not been at 

 all attempted, and the facts which relate or bear upon it are few in 

 number. 



The publication of the History of the Freshwater Fishes of Central 

 Europe by M. Agassiz has been looked forward to with interest by 

 British ichthyologists. Some of the plates for it were engraved so 



* See Mr. Yarrcll's figures in the work we have placed at the head of this notice. 



