NATURAL HISTORY OF BRITISH SALMONIDZ. 173 
of entomology, one of them exhibits a promise of future expansion 
never presented by the other. Not but that the latter, under 
favourable circumstances, is capable of reaching a considerable 
weight and size; but the larger he grows the less he really 
resembles the Great Lake type. His increase is lateral rather than 
longitudinal, as if the vertebrze refused to be parties in the process ; 
and I have seen quadrilateral monsters of this type taken in small 
bog lakes, which weighed from nine to ten pounds, though no more 
than a dozen or fifteen inches long. But they were nasty tenchy 
creatures to look at, bad for sport, and worse for the table. 
Our old friend /erox, notwithstanding his bad name, never 
makes a beast of himself in this fashion. No matter to what 
stature he grows, he never, till age overtakes him, loses his noble 
athletic and artistic proportions. In these characteristic qualities, 
he vies with salar and ¢rudfa themselves. Into rivers or brooks, 
except for the purpose of making them tributary to the propagation 
of his young, he never condescends to wander. Even in the lower 
reaches of rivers discharging into the lakes he inhabits, I have 
never met him in the summer months. Neither will he answer 
the call of inquisitive naturalists who expect to find him at home 
in small loughs, though contiguous to or connected by stream or 
river with large ones. Elbow- or, more correctly, fin-room he 
must have, or he will not prosper. There would appear, indeed, 
a certain ratio always to exist between him and the extent of water 
he requires. In this he, of course, only conforms to the supposed 
law of harmony which is said to prevail between all organisms 
and external circumstances. But why other little fishes in the 
same waters do not conform in the same way the philosophers do 
not tellus. It is probably certain, however, that in lakes less than 
three miles long, and half that in width, a genuine specimen of the 
ferox will not be found. The physical features, too, of the ample 
basin he loves to sport in, besides mere extent, have doubtless 
much to do with his health and happiness. Shingle beaches, 
marly bottoms, precipitous rocks, fathomless water valleys, and 
corresponding elevations of sharps or sunken islands, to which in 
the summer he resorts to have a charge at the sticklebacks, or a 
tumble at his favourite ephemerida, constitute some of the do- 
mestic requirements for his full development. As a variety he has 
no objection to a certain amount of bog shore; but it is obvious it 
does not agree well with his constitution—his fine colours suffering 
there, and his whole physiognomy becoming bilious and jaundiced. 
