COCCOLEPIS. 25 



there is so*ue displacement of the hgemals in the type, but ten can be clearly 

 counted in the second specimen as far as the origin of the caudal fin. The neural 

 arclies at the base of the upper caudal lobe are aborted, and a series of at least nine 

 slender rods above them support the large fulcra. The heemal arches in the basal 

 part of the same lobe are enlarged for the direct support of the dermal rays ; and 

 the series is continued for some distance along the lobe by very small though stout 

 ossified cartilages. 



The pectoral fins are missing, but all the other fins are well preserved in both 

 fossils. Ordinary fulcra are absent, but at the origin of each fin there are from 

 three to six simple, though distantly articulated rays, gradually increasing in length 

 to the apex of the fin, where the normal rays begin. These are also crossed by 

 distant articulations, and, in the caudal fin at least, they are distally bifurcated. 

 The pelvic fin is about as long as deep, arising nearly midway between the pectoral 

 arch and the anal fin ; its rays are shown to be not less than twenty in number, but 

 the supports are unfortunately not observable. The number of rays in the dorsal 

 fin is uncertain, but nineteen or twenty endoskeletal supports can be counted in 

 the second specimen (fig. 3). The anal fin is somewhat smaller than the dorsal, 

 with fourteen endoskeletal supports, of which the foremost is much the longest 

 (fig. 3). The extreme elongation of the upper caudal lobe is best seen in the second 

 specimen (fig. 3). 



The whole of the trunk is covered with small, thin scales, which have the 

 appearance of overlapping. They are, however, too obscure for detailed descrip- 

 tion, and it can only be noted that those of the lateral line in the caudal region 

 are slightly thickened, and form a conspicuous smooth band along the flank as far 

 as the beginning of the upper caudal lobe. Rather large tubercles of ganoine 

 ornament the scales, and are especially well seen in parts of the abdominal region. 

 A smooth thick ovate scale, pointed in front, occurs at the origin of the anal fin 

 in both specimens (fig. oa). The oat-shaped scales on the slender caudal lobe are 

 comparatively thick and smooth. 



Horizon and Locality. — Lower Purbeck Beds : Teffont, Wiltshire. 



2. Coccolepis, sp. Plate IV, fig. 4. 



Coccolepis or a related Pal^oniscid genus also occurs in the English Wealden, 

 as shown by an imperfect maxilla discovered by Mr. Charles Dawson, F.G.S., 

 in the Wadhurst Clay of Hastings (PI. IV, fig. 4). The upper margin of 

 the bone is incomplete, but the oral border is well preserved, and is seen to be bent 

 sharply downwards behind. The outer face of the bone is smooth on the anterior 

 extension, but very finely rugose in the hinder portion, where there is a tendency 



4 



