84 FISH AND FISHING IN SCOTLAND. 



fish of a doubtful character called parr. They may be caught 



with the ordinary bait for trout in every stream and pool 



from the sources, for example, of the Tweed to its junction with 

 the sea ; they were taken with the net in the tidal part of the 

 Nith, in my presence, and in numbers, in August and September ; 

 I have caught them in the rivers at all times of the year ; they 

 vary in size from two and a-half or two inches to six or seven, 

 and their growth seems independent of any season. But that 

 which is most remarkable, and is without an example in zoology, 

 is, that early in summer, and from this time to February and 

 March, many of the males of these dubious fishes have the milt 

 exceedingly developed ; the roe in the female remaining uniformly 

 and without any exception at its minimum. By supposing that 

 these dubious fish with embryonic markings are young salmon, 

 not yet grown into smolts, or, in other terms, which have not as 

 yet laid aside their embryonic colouring and characteristics, we 

 simply add other enigmas to those already existing. For how 

 comes it, that being fully as large as the smolt, they have not 

 left with it ? How comes it, that whilst still so young (not being 

 even as yet smolts), the male should have the milt enormously 

 developed, not only whilst in this state, that is, before he lias 

 even become a smolt, but long before the adult salmon itself ? 

 For the male parr has the milt fully developed quite as frequently 

 in July and August as in November and December. The fact is, 

 that these facts, for they are such, as I shall presently prove, not 

 merely upset the existing theories, but show that the question of 

 the parr is one involving the highest questions in animal physio- 

 logy, and explicable, in all probability, only by an appeal to the 

 laws regulating hybridism and transcendentalism in animal life. 



It has been said that parrs have been placed in ponds, and have 

 grown into salmon. That they may grow into fish strongly 

 resembling salmon, I am not disposed to doubt, although I do 

 not feel quite sure that the experiment has ever been fairly 

 made ; but this does not prove them to be true salmon. The mule 

 grows up to something strongly resembling a horse. The fish 

 grown from parr is found to be prolific for at least one genera- 

 tion, " which could not be were it a hybrid, or the parr from 

 which it grew, a hybrid." Now those who argue thus, take for 



