REVISIOX OF THE FISH FAMILY LIPARIDAE 157 



of generic value. They are, however, of great value in distinguishing 

 species or groups of species. 



I have not attempted to utilize to any great extent the modifications 

 in shape, size of pulp cavity, and numbers in the teeth of these species. 

 When the time comes for a more intensive study of the fishes, the 

 teeth will probably be found to offer a profitable line of research. 

 The data that we have at present is not satisfactory for the reasons 

 that we do not know the amount of variation in the teeth of the 

 young and adults and between the two jaws and different sections 

 of each jaw. 



Dorsal fin. — The dorsal fin in this genus has not been studied 

 sufficiently to warrant the use of the number of rays in distinguishing 

 species. The number of dorsal rays varies from 48 to 66 or more. 

 We have made no attempt to study the amount of specific variation. 

 The rays are extremely delicate and difficult to count accurately. 

 For these reasons the writer has made no attempt to use the number 

 of dorsal and anal rays in separating species. Dorsal fin is unnotched. 



The segmentation of the anterior dorsal rays was investigated 

 in a number of species. The anterior rays are divided but unseg- 

 mented. The number of unsegmented rays varies among the 

 difi'ercnt species. The species examined, with the number of 

 unsegmented dorsal and anal rays, are listed below: 



Dorsal Anal 

 fin fin 



co-pei 18 16 



Do (?) 8 



Do 13 10 



deani 9 4 



Do 11 4 



cephalus 10 6 



Anal fin.-— Wl\a.t has been said concerning the number of dorsal 

 rays applies equalh' well to the number of anal rays. The number 

 of anal rays varies from 42 to 60. 



Caudal fin. — In studying the caudal fin attention should be dii'ected 

 to the number of rays and the connection with the dorsal and anal 

 fins. The number of rays varies from three or four to eight. Appar- 

 ently there is little variation in the number for each species. This 

 is a question which needs further study. Apparently there ai'e no 

 rudimentary rays at the base of the caudal as in Liyaris. 



The caudal fin is always distinct. The dorsal and anal are never 

 continuous as frequently described. The connection between the 

 anal and the caudal varies from 0.3 to 0.6 of the length of the latter. 

 The connection with the dorsal and anal is usually very gradual, 

 though somewhat abrupt in a few species. 



Pectoral fin. — The pectoral fin presents some of the most important 

 specific characters. These have been used freely in the key to the 



