EDWIN CHAPIN STARKS 37 



head is from 1 to 1^ diameters of the eye less than the length of the head. 

 The depth of the head at the point of the supraoccipital is equal to the 

 length of the snout. The interorbital space is contained 2}^ times in the 

 head, and the length of the snout from 1^ to \fi times. • The distance 

 from the anterior nostril to the tip of the snout is equal to the interorbital 

 space. The middle of the interorbital space is only a trifle higher than the 

 supraorbital rim, while the intermediate space between these two points is 

 somewhat sunken on each side. The eye, inside of the eyelids, is contained 

 from 9 to 10 times in the head, and 3^^ to 4 times in the interorbital space. 

 The band of teeth on each side of the mandible is contained 3^2 times in the 

 interorbital space, and the width of the lower lip 2^/2 times. The barbel 

 does not reach to opposite the posterior edge of the lip, and is equal ta 

 the space between the eye and the posterior nostril. 



The distance from the tip of the snout to the first dorsal spine is con- 

 tained from 2ys to 2^/2 times in the length of the body. The vent is mid- 

 w^ay between the base of the caudal and the pectoral spine. The depth of 

 the body in front of the dorsal spine is contained from 4 to 4^^ times in the 

 length, and the greatest width from 3 to 3^4 times. The caudal peduncle 

 in front of the adipose dorsal is as wide as it is deep. The first dorsal spine 

 is a trifle less than the length of the head, and when the fin is reclined its 

 tip does not reach to the middle of the last ray. The last ray is equal to 

 the length of the snout, and for a short distance near its base it is adnate 

 to the back. The tips of the last rays broadly overlie the adipose dorsal, 

 reaching at least to its middle. On the posterior margin the dorsal fin is 

 convex. The length of the pectoral spine is contained from 3 to 3^4 times 

 in the length of the body, and almost a third of its length extends past the 

 base of the ventral. The ventrals reach well past the posterior end of the 

 anal base, or half way or more from their base to the caudal fin. The anal 

 has a spine and 4 soft rays, and the tips of its rays do not reach so far 

 back as the dorsal rays, but reach half way, or nearly, from their base to the 

 caudal. The lower caudal lobe is longer than the upper, and the lowest 

 branched ray reaches nearly to the tip of the lower simple ray, which is 

 scarcely filamentous at the tip. The lower simple ray is contained from 

 2}i to lyo times in the body, the upper ray from 2^ to 2^ times. 



The supraoccipital is bounded behind by a single plate. Two upper 

 rows of plates are slightly carinate, and four plates extending back from the 

 pectoral are bluntly carinate ; the carinations are scarcely evident elsewhere. 

 The longitudinal spinules grow coarser on the caudal peduncle, and are 

 coarser and less numerous than in P. plccostomus. There are 25 or 26 



