FISHES — PLEUEONECTIDAE — PSETTICHTHYS SORDIDUS. 



155 



gradually in height to a certain distance, then diminishing again rapidly to the terminus of the 

 fin, which does not extend to the base of the caudal. The origin of the anal is situated some- 

 what posteriorly to the base of the pectorals. An acute and inconspicuous spine, directed 

 horizontally forwards, may be observed at the anterior margin of that fin ; the soft rays 

 increase gradually in size for a given distance, to diminish posteriorly exactly as is the case in 

 the dorsal, terminating evenly with the latter fin. The peduncle of the tail is somewhat 

 dilated near the insertion of the caudal, the central rays of which being the longest, the 

 posterior margin of that fin is necessarily convex. The pectorals are small and the ventrals 

 smaller still ; both being exteriorly rounded when expanded. The extremity of the ventrals do 

 not reach the anterior margin of the anal when bent in that direction. The insertion of the 

 same fins is placed in advance of the base of the pectorals. The branchiostegals are six on 

 either side ; the branchial apertures being continuous under the throat. 



Br. VI : VI ; D 78 ; A 60 ; C 4, 1, 6, 6, 1, 3 ; V 6 ; P 12. 

 The rays of the dorsal and anal fins being undivided ; those of the other fins bifurcated or 

 dichotomised. The scales are very small, longer than deep, and extending over the head and 

 vertical fins. The lateral line, from the scapular region, take a declivous course until it 

 reaches the middle of the flank posteriorly to the tip of the pectorals ; hence straightway to 

 the caudal fin. The total length of the specimen described is four inches and three quarters. 

 The ground color of the right side is cinereous interspersed with crowded black dots, which are 

 occasionally confluent or irregularly grouped into patches. The left side is uniform dull yellow. 



List of specimens. 



2. PSETTICHTHYS SORDIDUS, Grd. 

 Plate XLb. 



Spec. Char. — Body elongated and sub-elliptical. Eyes large, situated on the lefL side; interocular space very narrow. 

 Jaws nearly even when mouth is closed. Posterior extremity of tlie maxillary extending to a verticalline intersecting the 

 pupil. Anterior rays of dorsal fin gradually increasing in height. Dorsal and anal fins nearly even posteriorly. Origin of 

 anal situated on a line passing immediately behind the base of the pectorals, and preceded by a very small spine. Scales 

 moderate sized ; lateral lino almost straight from head to tail . Ground color of a soiled yellow ; the scales being margined 

 with black. 



Srn .—PsettklUhys sordidws, Grd. in Proc. Acad. Nat. Sc. Philad. VII, 1854, 142 & 155. 



The general outline is sub-ellipsoid ; the total length being nearly five inches and a half, in 

 which length the greatest depth enters a little short of three times. The head constitutes 

 nearly the fourth of the total length. The gape of the mouth is oblique, and when closed the 

 extremities of the jaws are even ; the posterior extremity of the maxillar bone extending to a 

 vertical line which would intersect the pupil. The teeth are slender, unequal, sub-conical, and 

 acerated, occupying either side of the jaws. The eyes are proportionally large, sub-elliptical, 



