REVISION OF THE FISH FAMILY LIPARIDAE 97 



pore on the snout may be high up and nearly between the nostrils, 

 as in C. pellucidus and C. tracJiysoma, or far forward on the snout 

 near the anterior pores, as in C. hathycoetus and C. roseqfuscus. In 

 some of the species the maxillary and mandibular pores are sunken 

 in pits. In C. sinensis and a few other species the anterior mandibular 

 pores have a common opening. In C. hathycoetus, a black species, the 

 pores appear as white dots. A more extensive study of the pores is 

 desirable as they will probably be found to be of considerable 

 taxonomic importance. 



Many of the species of Careproctus as of Liparis have rudimentary 

 pores on the sides of the body and on the nape. These pores could 

 not be detected on many of the species with a thin, lax skin and are 

 probably absent. They are the most readily seen on the generalized 

 species C. pycnosoma, C. curilanus, and C. howersianus. 



Gill slit. — In the majority of the species of Careproctus the gill slit 

 is confined to the region above the base of the pectoral. For this 

 reason the gill slit is not of such taxonomic importance as in Liparis. 

 In the latter genus the gill slit, in the majority of the species, extends 

 down in front of the pectoral and varies greatly in size. The variation 

 in the size of the gill slit, when confuied to the region above the base 

 of the pectoral fin, is so slight as not to be of taxonomic value. 



The extreme variation in the gill slit is almost as great as in Liparis. 

 In C. ostentum the gill slit extends down in front of 14 pectoral rays. 

 The gill membranes are frequently torn so that it is difficult to decide 

 whether the slit is confined to the region above or extends down in 

 front of the fin. The variation within some species is such that the 

 gill slit in some specimens is above the pectoral fin and in other 

 specimens extends down in front of the upper one or two rays. 



Teeth. — The teeth may be either trilobed or simple. In some of 

 the species both kinds of teeth are present. The teeth do not present 

 any characters of generic value. We can rouglily divide the genus 

 into three groups of species based on the character of the teeth but 

 these groups grade insensibly into each other. These three groups 

 may be defined thus: (1) Teeth strongly trilobed; (2) teeth weakly 

 trilobed to simple; (3) teeth simple, lanceolated, recurved, the anterior 

 teeth appearing as large as the inner teeth. 



The arrangement of the teeth on the jaw varies among the different 

 species. They are always arranged in oblique rows. The inwardly 

 diverging rows are, in some of the species with simple teeth, very 

 oblique and difficult to count. In such species the band of teeth is 

 usually narrow. A good example of this type of dentition is found 

 in C. gilberti. The cutting surfaces presented by the bands of teeth 

 are typically oblique. This is because the anterior teeth are smaller 

 and placed lower on the outer surfaces of the jaw bones. A striking 

 exception to this type of dentition is found in C. colletti and related 



