PREFACE. 



In this work the writer has endeavored to g-ive concise descriptions 

 of all the fish known to inhabit the waters of the Province of Ontario. 



The classification and sequence of groups adopted is that of Jordan 

 and Evermann, to whom I am also chiefly indebted for the technical des- 

 cription. 



In the description of species the expressions "head 4" or "depth 4" 

 m.ean that the leng-th of the head in one case, or the g-reatest depth of 

 the body in the other, is contained 4 times in the leng-th of the fish 

 measured from the tip of the snout to the end of the last caudal vertebra, 

 the caudal fin being- not included. The size of the eye and the length of 

 snout and other head parts are compared with the length of the side of 

 the head, unless otherwise stated. ; thus "eye 5" means that the horizon- 

 tal diameter of the eye is 1-5 the leng-th of the head, "scales 5-64-7" 

 means that there are 5 rows of scales between the base of the dorsal fin 

 and the lateral line (the scale in the lateral line excluded), 64 oblique tran- 

 verse series crossing- the lateral line and 7 horizontal series between the 

 lateral line and the base of the anal or the vent. 



The fin formulae are shortened as much as possible; thus "D. 10," 

 "D. IV, 9," or "D. VIII-13" means that in the first case the fish has 

 a sing-le dorsal fin of 10 soft or articulated rays; in the second case a 

 singfle dorsal fin of 4 spines and g soft rays ; and the last indicates a fish 

 with two dorsal fins, the first composed of 8 spines and the second of 13 

 rays. 



Spines are always indicated in roman letters and rays in arabic 

 letters. 



The measurements given are intended to apply to the average of 

 mature fishes. Young- fishes usually have the depth less, the head and eye 

 larg-er and the mouth smaller in proportion than adult examples of the 

 same species. 



The coloration and marking of fishes is extremely variable, no two 

 individuals being exactly alike; and not only so, but each individual 

 chang^es its color from time to time in accordance with its surroundings. 

 All color descriptions as given herein are intended to apply to the normal 

 adult in its hightest development as found in the waters to which it is 

 best adapted. 



C. W. NASH. 



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