How to Identify a Fish 



case a single dorsal fin of 5 spines and 9 soft rays; and the last 

 indicates a fish with two dorsal fins the anterior of which is 

 composed of 8 spines and the other of 1 3 soft rays. Spines are 

 always indicated by roman letters and rays by figures. The 

 abbreviations for the other fin formulas are similarly explained. 



The measurements given in the text are intended to apply to 

 the average of mature fishes. Young fishes are usually more 

 slender, the head and eye larger, and the mouth smaller than in 

 adults. 



Those who wish to learn more of what has been written regard- 

 ing American fishes are referred to the present writers' " Fishes of 

 North and Middle America," a work in 4 volumes of 3,313 pages 

 and about 1,000 illustrations recently published as Bulletin 47 of 

 the United States National Museum; to the "Fisheries and Fishery 

 Industries of the United States " by Dr. George Brown Goode, 

 published in 1884 as a part of the Tenth Census Reports; and to 

 the various Annual Bulletins and Reports of the United States Fish 

 Commission. 



XXXIV 



