REVISION OF THE FISH FAMILY LIPARIDAE 



155 



Disk absent; nostril single; teeth trilobed to simple; suprabrancliial 

 pores apparently single in all the species; pyloric coeca present, i^ 

 small numbers; pseudobranchiae absent; ^* branchiostegals 6. 



MODIFICATION OF CHARACTERS 



Body. — In the species of Paraliparis the body is never depressed 

 as in the species of Liparis. It is compressed but never attains the 

 depth of some of the species of Careproctus, The shape of the body 

 varies among the different species. In P. copei it is moderately stout 

 and elongate, in P. liolomelas very heavy anteriorly and attenuate 

 posteriorly and in P. mento very slender. Many of the species have 

 the posterior part of the body attenuate, the vertebrae being very 

 small and evident through the skin. 



The bodies of the species of Paraliparis are typically frail and soft 

 but lack the excessive amount of pseudotissue found in many species 



Figure Si.— Elassodiscus tremebundus. Teeth from coTrPE 



of Careproctus. Paraliparis is more typically a deep-sea genus than 

 Careproctus . Pseudotissue apparently is more common to the shal- 

 lower water species of the two genera. 



The shape of the body and the proportional measurements of head 

 and body have been used in but a general way in distinguishing the 

 species. 



Head. — The head furnishes a number of useful characters. It is 

 typically compressed. The width of the head is seldom if ever equal 

 to the depth. The snout is usually deep and abrupt. It distinguishes 

 a few of the species by projecting slightly. The profile of the head 

 is typically rather low and rises gradually to the nape. P. cepJialus 

 is distinguished by the occiput being greatly swollen. The mouth is 

 usually horizontal, but P. cepTialus and a few other species are dis- 

 tinguished by the mouth being at an angle. When the mouth is on 

 an angle the lower jaw may be heavy and project as in P. mento. 



w See discussion of this character. 



