NO. 31 



NEW GENUS AND SPECIES OF EEL REID 



cal teeth, followed by an edentate notch in the upper jaw, which re- 

 ceives the expanded tip of the lower jaw, bearing teeth similar to 

 those on the head of vomer. Shaft of the vomer with 6 or 7 slightly 

 enlarged conical teeth on the midline with smaller teeth on either side 

 continuing backward on the shaft in an irregular double series to 

 below the posterior nostril and thence in a single series to below 

 middle or posterior edge of eye. Maxillary band of teeth divided by 

 a longitudinal naked groove, on the inner side of which is a single 

 series of conical teeth so closely set as to form almost a cutting edge. 

 These teeth lean strongly inward and extend from opposite the rictus 

 of the jaws forward to opposite the middle of the larger teeth on the 

 shaft of the vomer, where they terminate abruptly. The outer band 



Fig. I. — Paraxcnomystax bidcntatus, n. sp. 



of maxillary teeth are in 5 or 6 irregular series, becoming progres- 

 sively smaller externally where they are directed obliquely outward. 

 This band is strongly convex in cross-section, the dentigerous surface 

 evenly curved from the horizontal to vertical plane. Mandibular teeth 

 similarily divided, though the edentulous groove is notably narrower. 

 Tip of the mandible with a cluster of slightly enlarged conical teeth 

 about equal to those on the head of the vomer. Lips wholly absent ; 

 all the lateral teeth as well as those on the head of the vomer are fully 

 exposed when the mouth is closed. Anterior nostrils tubular, situated 

 laterally and well behind tip of snout. Posterior notrils slitlike, before 

 middle of eye and situated entirely in the posterior fourth of the 

 snout length. Origin of the dorsal fin above anterior third of the pec- 

 toral length, the fin rather high, rays progressively longer and less 

 erectile posteriorly, length of the rays above vent about half the 

 depth of body at this point. Anal similar, but much lower, both con- 

 fluent with caudal fin, which is lanceolate. Branchial openings wide, 



