538 



ME. E. T. XEWTOX OX PISH-BEAIAIXS FEOil THE 



the first and second thirds will be the attachment of the' ventral fin ; 

 and at the point between the middle and hinder thirds the beginning 

 of the anal fin. The form of the ventral fin is best shown by speci- 

 men nnmber four (PI. XXII. fig. -4). The pectoral, ventral, and anal 

 fins are of moderate size ; but the single dorsal fin is large, with strong 

 and seemingly articulated rays, while its anterior border is provided 

 with well-developed fuleral scales. This fin begins nearly opposite 

 the ventral fin, and seems to have extended backwards almost to 

 the anal fin ; but the hinder part being broken away, its exact 

 extent cannot now be seen. Several ridges and grooves extending 

 downwards from the dorsal fin indicate the presence of strong 

 interspinous bones. The tail-fin is not preserved in number one 

 (fig. 1) : but the fragments of tails (figs. 5, 6) show that the 

 upper lobe was larger and stronger than the lower, and had its 

 upper margin furnished with particularly large fulcra (see also 

 fig. 2), and its sides covered with elongated spindle-shaped scales. 

 The sides of the body are covered with comparatively strong, 

 shining, rhomboidal scales, which in the middle region are large 

 and from two to three times as long from above downwards as 

 they are from back to front. Towards the tail, as well as above 

 and below, the scales become smaller and nearly equal- sided. The 

 surface of the scales is smooth and shining ; but on some of them, 

 especially towards the tail, two or three indistinct oblique ridges 

 run from front to back. In the first specimen (fig. 1) the hinder 

 border of the scales is imperfect, and it is not clear whether this 

 was smooth or denticulate ; but specimen number seven has some 

 at least of the body-scales finely denticulate (fig. 7). One of the 

 tails (fig. 6) also shows that in some of the scales the indistinct 

 ridges end in points on the hinder margin. 



Unfortunately none of the specimens give any clear information 

 as to the form of the head, or of any of its bones or plates. The 

 restored outline of figure 1 is hypothetical, and is merely added to 

 give a better idea of the position of the parts preserved. In the 

 position where the bones of the head might be expected (figs. 2 and 3) 

 there are only indistinct traces, which may be bones partially 

 dissolved, and these appear granular on account of the sandy 

 matrix beneath. Specimen number 2 shows what seems to be a 

 comparatively large conical tooth near the end of the snout (fig. 2, a). 

 In the opercular region there is a broad plate (b) with two 

 tooth-like prominences at its hinder border, which may be one of 

 the opercular bones ; and a strongly striated plate (c) seen a little 

 further back will probably bear a like interpretation. The seventh 

 specimen also shows a similar striated plate. 



The only ganoid fishes which have been described from British 

 Triassic strata are the unique specimen of Dipteronotus ci/phus, 

 from the Bunter of Bromsgrove, described by the late Sir Philip 

 Egerton *, and the PaJceoniscus superstes, also described by the same 

 author t, from a specimen found by Mr. Brodie at Bowington, in 



* Quart. Journ. Geol. Soc. vol. x. p. 367 (1854). 

 t Ibid. vol. adv. p. 164 (1857). 



