TRANSACTIONS OF THE SECTIONS. 105 



The large-leaved Neuropteris cordata, a Sphenopteris with a fucus-like leaf of large 

 size, and another quite filiform, have also been found by the authors. The follow- 

 ing are the more interesting ichthyic remains, as far as they can identify them by 

 Agassiz : — 



Dipterus. Part of the head, and plates. 



Palaoniscus. Scales, and a portion of the fish (ornatmimus, Duvernoyii). 



Gyrolepis. The hinder half of the fish. 



Calacanthus. Scales and fins. 



Platysomus. Fragments of the fish, and numerous scales. 



Rhizodus. Most of the fish, and the sharp- and curve-pointed striated teeth. 



Holoptychius. Very large plates and parts of the fish, the upper jaw with double 



rows of large and small striated teeth. 

 Ctenodus. Two or three pieces. 



Megalichthys. The plates are very common as well as the teeth, a cranial plate 

 6 inches wide, vertebra; 2 inches; also the jaw with teeth, and the tail 

 found by Mr. Ward. 

 Saurichthys. Teeth swollen at the bottom, striated, and more curved than the 



commoner teeth of the last genus. 

 Ctenacanthus. The armature is not rare, a fine and perfect one found by Mr. 



Ward. 

 Hybodus. The teeth with crumpled base, one large middle cusp, and two or 



three side ones on each side. 

 Diplodus. The supposed teeth are very common, with three or more fangs. A 

 tooth straight, compressed, lanceolato-conical, 1 j inch in length : if it belongs 

 to Diplodus, the size must be unusual. 

 Ctenoptychius. The beautiful teeth are not very rare ; there appears to be 

 numerous species (apicalis, pectinabm, and denticidatus). A tooth of, appa- 

 rently, a new genus, very small, with truncate base and eight or more cluster- 

 ing slender-pointed cusps at irregular altitudes. 

 Petalodus. Remains of several species. 



Helodus simplex. Base of teeth excavated, the summit simple and blunt. 

 Pleur acanthus. These curious armatures are rare, but we have found one veiy 

 perfect in cannel ; some imperfect specimens have the central part compressed, 

 and the processes less marked. 

 Onchus (?). These sword-shaped rays or spines, moulded on the concave edge, 



are extremely common. 

 Orthacanthus. These formidable weapons are frequent, and very long, a foot or 

 more ; they are difficult to get out unbroken. A smaller and more conical 

 armature without term. 

 Leptacanthus. 



Gyracantkus. Common, and of two or more species. 

 Besides the above, numerous fragments have been collected, of more or less 

 interest, some considered to be novelties by Sir P. Egerton : also nine or ten species of 

 the bivalve Anthracosia. The authors are rather reluctant to give names, but the 

 following epithets may almost suffice to distinguish them : — A. triangularis, dactylus, 

 unio, anodon, retrocompressa, alata, mictda, oblonga. costata. 



The hillocks raised by annelides, ripple-marks, and very large impressions of 

 bivalves of two or three forms occur in the flagstone of the millstone grit ; also 

 transverse sections of plants, either round or obliquely indicated, as if blown 

 down. 



From the mountain limestone, occupying about 40 square miles, more than 200 

 species of Mollusca have been collected, but this principally by a friend, Mr. 

 Carrington, a village schoolmaster. Amongst the more interesting species are 

 Conularia, species of Pteronites, Pleurorhynchus ; rare Pleurotornarise, Goniatites, 

 and Nautili ; the OrtJi. paradoxus, or one similar to that from Ireland figured by 

 Sowerby; abimdance of corals; many pelvic plates of Crinoida, and about ten species 

 of Trilobites, all small, and rarely entire. The latter most abound with the fry of 

 Terebratulse. Mr. Carrington has also foimd traces of fish. The limestone shale 

 has some obscure impressions of bivalves. With respect to vegetable remains, 

 little has been discovered: certain supposed stems or twigs, of an enamelled 

 appearance, are siliceous when chemically examined ; and the received opinion 



