BRITISH FOSSILS. 



3 



diately over tlie attachment of the ventral fins. The middle of the 

 fin is coincident with the centre of the dorsal line. It is supported 

 upon seventeen strong interneural spines, and contains a like number 

 of rays. These are entire for some distance from the base ; they 

 then bifurcate, and are transversely jointed at small intervals. The 

 anal fin is situated nearer to the ventrals than to the lower lobe of 

 the caudal fin. It is attached to eight ossicles, and is composed of 

 as many rays, agreeing in all respects with those of the dorsal fin, 

 except in being shorter and more slender. There are traces of 

 border scales on the first rays of both. The caudal fin is broad and 

 rounded posteriorly. In form it resembles the tail of the recent 

 Lepidosteus. A few fin rays, constituting the upper lobe, spring 

 from the neurapophyses of the sixth, seventh, and eighth vertebrse, 

 reckoning from the caudal extremity of the column. These are 

 single, without bifurcations or transverse joints ; the remainder, 

 about twenty in number, are supported by the flattened extremities 

 of the elongated haemapophyses. They are coarse, with three or four 

 bifurcations and frequent joints. The fin is completed below by a 

 few single rays springing from the hsemapophysis of the fifteenth 

 vertebra. This is the longest of these processes ; those behind it 

 decrease in gradation to the extremity of the column. The scales 

 are large, and rounded posteriorly ; they difier from the scales of 

 MegaluTus lepidotus in having the longitudinal diameter greater 

 than the transverse. They are thick, and of a coarse texture, and 

 are covered exteriorly with a thin coat of enamel, ornamented with 

 fine concentric rings. They have no rib or articulating process 

 on the inner surface. In this respect, and in their imbricated 

 arrangement, they very much resemble the scales of a Ccelacanthus. 

 This very interesting addition to our list of British fossil fishes I 

 have designated by the specific name of Megalurus Damoni. 



Locality. — Found by Mr. Damon in the Purbeck strata at Bin- 

 ombe, about three miles north of Weymouth. 



Explanation of Plate. 



Fig. ] . Megalurus Damoni, size of nature. 

 Fig. 2. Counterpart of do., size of nature. 

 Fig. 3. Scale, magnified. 



P. DE M. Grey Egerton. 



February 1857 



