﻿pal2eoniscid;k. 517 



depth of trunk contained about five and a half times in the total 

 length. Head and opercular apparatus occupying one quarter of the 

 total length ; snout acutely pointed ; teeth long and slender, sharp, 

 and somewhat bent inwards ; tuberculations of cranial roof regular 

 and closely arranged, strite upon maxilla and mandible also numerous, 

 but irregular, those of the expanded hinder portion of the maxilla 

 chiefly concentric with the posterior arid upper margins, those of 

 the mandible chiefly longitudinal, but short, irregularly anastomos- 

 ing and bifurcating. Pelvic fins two-thirds as large as the pectorals, 

 arising nearer to the anal than to the latter ; dorsal fin slightly 

 larger than the anal, terminating opposite the anterior rays of this 

 fin. Scales with prominent, sparse, superficial ridges of ganoine. 

 Form. Sf Loc. Lower Lias : Dorsetshire. 



P. 3485. Type specimen described by Egerton, and figured loc. cit. 

 pi. ix. : Lyme Regis. The pectoral fin-rays are rightly 

 noted as devoid of transverse articulations, though such 

 are indicated by error in the figure ; and there is some 

 inaccuracy in the drawing of the superficial ornament of 

 the jaws and branchiostegal rays. The striations upon 

 these bones are not regular and parallel, but elongate len- 

 ticular in form, closely interlaced, and apparently some- 

 times branching. As remarked by Egerton in the appen- 

 dix to his description, the apparently small size of the 

 anal fin is due to its imperfect state of preservation. 



Ennishillen Coll. 



P. 557. An almost complete specimen described (with figure of 

 caudal region) by Egerton, loc. cit., appendix, p. 2, pi. ix.* ; 

 Lyme Eegis. The head is seen partly from beneath, 

 partly from the left side, and displays the jaws, dentition, 

 branchiostegal rays, opercular bones, and a fragment of 

 the cranial roof. The latter bone is tuberculated ; the 

 operculum and suboperculum show only lines of growth 

 with a few scattered pittings ; and the jaws and branchio- 

 stegal rays are characteristically striated. Some inferior 

 external bones, apparently imperfect infraclavicles, are 

 marked with coarse short rugae and rounded tubercles. 

 The supposed ossified vertebral centra are either small 

 pleurocentra and hypocentra, or (as seems more probable) 

 merely the expanded bases of the arches ; and the upper 

 caudal lobe is of the ordinary Palaaoniscid and Acipen- 

 seroid type. The fins and scales do not require further 



