538 MR. A. SMITH-WOODWARD ON THE [June 23, 



is represented in Plate XLVII. fig. 3. This bone is of an elon- 

 gated triangular form, tlie apex directed anteriorly, and the short base 

 supporting the rays of the fin ; it exhibits a little rounded process 

 at the posterior extremity of the inner border, for articulation with 

 its fellow of the opposite side. Tlie pelvic fin is, as usual, somewhat 

 smaller than the pectoral, though still tolerably robust; and its 

 characters are well seen in the original of Plate XLVI. fig. 1. It is 

 opposed to the hinder part of the dorsal, and consists entirely of soft 

 jointed rays, to the number of about 12 in R. buccalis. 



The dorsal fin is relatively short, and is supported upon a series of 

 strong interspinous bones, of which the most anterior has the widest 

 expansion (jR. brama, Plate XLVI. fig. 1). In front, there are about 

 three small spinous rays, followed by two others of larger size ; but 

 the maximum length is attained by the first succeeding soft ray, and 

 from this there is a gradual shortening backwards. In one species, 

 R. latus, the anterior soft ray is extraordinarily powerful, and divided 

 for more than half its length by closely approximated, oblique 

 sutures. 



There is no trace of an adipose dorsal fin, notwithstanding the 

 perfection with which some of the soft parts are preserved. 



The anal fin is very small, and the rays in R. buccalis are about 10 

 in number ; these are much divided, as shown in Plate XLVI. fig. 1. 



The caudal fin, as already mentioned, is deeply forked, and the 

 median rays are very short, only slightly extending beyond the much- 

 elongated posterior termination of the body. In one specimen, 

 indeed, probably referable to R. buccalis (no. P 1958 a), the median 

 rays do not constitute more than a little delicate fringe, sharply 

 marked off from the two main lobes of the fin (Plate XLVII. fig. 2), 

 though this may quite possibly be an abnormal appearance due to 

 the circumstances of fossilization. 



The scales are preserved in almost every specimen, but it is only 

 rarely that they are well displayed, owing to abrasion and fractures 

 produced in the removal of the surrounding stony matrix. They 

 are deeply imbricated, but it does not seem possible in any case to 

 determine the number either of the transverse or longitudinal series ; 

 nor can anything be stated with certainty as to the variation in size 

 in different regions. The exposed portion of each scale is beautifully 

 ornamented with radiating ridges, which are strongest near the 

 periphery (Plate XLVI. fig. 6) ; and these sometimes impart to the 

 hinder border of dilapidated examples the appearance of being 

 ctenoid. The superficial layer of the scales, however, is nearly always 

 destroyed. The lateral line is only observed where the ornamented 

 portions of the scales are broken away, and would thus not be visible 

 in the living fish. A small " axillary appendage," of elongated 

 form, is to be noted in one or two specimens above the pectoral fin 

 (Plate XLVI. fig. 7). And, lastly, there is the interesting fact that 

 the dorsal and caudal fins are covered to some extent by smaller 

 scales than those investing the body, these being extremely thin and 

 exhibiting no markings beyond the concentric lines of growth (B. M. 

 no. 28616). 



