282 



I'ltovEKimtQB OF tin: \ IT10NAL \n si:i \i. 



vol. 38. 



Measurements of Pleuronichthys verticalis. 



Length of body without caudal, in mm 



Depth of body in hundredths of length 



Length of head 



Longitudinal diameter of upper orbit 



Distance across both orbits 



Length of maxillary 



Ventral of eyed side posterior to that of blind... 



Length of caudal peduncle 



Depth of caudal peduncle 



Number of dorsal rays 



\iial rays 



Scales, below lateral line, in longitudinal series. 



Gill-rakers on first gill arches 



220 



54 



25 



9 



10 



5.5 



2 



5 



14 



70 



48 



96 



3+6 



3+6 



PLEURONICHTHYS NEPHELUS Starks and Thompson, new species. 



This species has a lower number of scales than any other of the 

 geuus; its low interorbital ridge is free from spines; and the ventral 

 of its cv< i d side is not so far posterior to its fellow of the opposite side. 

 From Pleuronichthys ccenosus it may be known in addition by the 

 smaller diameter of the upper orbit. 



Head from 3£ to 4 J in length of body without caudal; depth If 

 to 2. Upper orbit 3 to :\h in head; maxillary 3^ to 4; length of 

 caudal peduncle measured to marginal caudal rays 7 or 8; its depth 

 1£ to 2. Number of dorsal rays 66 to 75; anal rays 47 to 56; scales 

 in series below lateral line 66 to 75 ; gill-rakers 3 or 4 + 9 to 1 1 (in one 

 specimen 12). 



Body very symmetrical in dorsal and ventral contours, which are 

 evenly curved from caudal to tip of snout. The interorbital ridge is 

 low and without prominent spines; at the anterior end are sometimes 

 very slight indications of tubercles, and the position of the posterior 

 spine i- marked by little more than a slight angle, except in the type 

 (the Largest specimen) there is a blunt tubercle. The eyes are small, 

 not vei \ prominent, and nearly opposite to each other. The nostrils 

 of the left side are close to the dorsal, and those of the right are not 

 so far removed from those of the left as usual. The maxillary is not 

 covered by the preorbital bones. There is a row of teeth on the v\n\ 

 side of the mandible, but none on the preinaxillary of that side, and 

 three or four rows on the blind side of each jaw. 



The dorsal tin arises a little above the level of the tip of the snout. 

 The dorsal and anal extend so close to the base of the caudal that the 

 tips of their last rays nearly or quite reach to the bases of the marginal 

 caudal rays. The ventrals are more nearly opposite to each other 

 in insertion than in other species of the genus; the distance of that 

 of the vycA side behind that of its fellow of the opposite side is con- 

 tained three or four times in the length of the maxillary. The caudal 

 lin is very conspicuously broad and round in outline. 



The scales are large and unimbricated over the entire body, some- 

 times much buried in the skin, the lateral line ascending less than 

 Usually anteriorly, with a short anterior branch, and a long posterior 

 one ending under the middle of the dorsal. 



