NOTICES OF NEW BOOKS. L199 
new, the facts bearing upon them which have been collected by 
the author in many places seem to throw a new light upon the 
questions at issue. 
Four of the chapters deal with the Natural History of the 
Salmon, Trout, Sea Trout, and Grayling; the remaining chapters 
contain directions when, where, and how to fish for all these 
in turns, with many entertaining reminiscences of good and bad 
days’ sport enjoyed by the author, and an attempted explanation 
of the causes which he supposed contributed to his success or 
the want of it. : 
At p. 168 Dr. Hamilton discusses the subject of variation 
in the colour of Trout, and how produced :—‘‘ Some with dark 
backs, silver sides, and black spots: others, splendid fellows, with 
yellow sides, and red spots predominating.” 
It has been noted, he says (p. 169), that in the swift-running 
streams over gravelly beds the fish for the most part have red 
spots and yellow flesh—perhaps owing to the greater exposure to 
light; in the deeper rivers and more sluggish streams Trout are 
more black-spotted. 
After examining the opinions of previous writers on this 
subject, Dr. Hamilton concludes (p. 173):—“ Taking all the 
various causes for change of colour in the Common Trout, I 
can only come to the conclusion that there is only one species of 
the Salmo fario in Great Britain, and that the so-called species 
of Couch and other authors are only varieties of this fish.” 
The Grayling appears to have received its name thymallus 
from the odour of the fish when first taken out of the water. 
“Some people,” says our author, “are unable to distinguish this 
peculiar smell, but it is unmistakable. I have caught hundreds 
of Grayling, and have never found it absent in any fish over half 
apound. But it is more ‘like the smell of cucumber than thyme 
much the same as that which emanates from the Smelt.” 
Three peculiarities of this fish strike the observer at once— 
the triangular pupil of the eye, the large beautiful violet-coloured 
spotted dorsal fin, and the two longitudinal orange-coloured 
stripes extending from each pectoral fin. The name Grayling is 
said to be a corruption of “gray lines,” from the longitudinal 
lines along the body. It is called “Oumer” in Northumberland, 
and the smaller fish prior to breeding are known on the Teme as 
_“Shutts” or “Spots.” Salviani says the name Umbra is derived 
