﻿PTERASPID^E. 



171 



1858. Pteraspis banksii, T. II. Huxley, ibid. vol. xiv. p. 274, pi. xv. 

 1865. Cyathaspis banksii, E. R. Lankester, Rep. Brit. Assoc. 1864, 



Trans. Sect. p. 58. 

 1868. Cyathaspis banksii, E. R. Lankester, Fishes Old Red Sandst. 



pt. i. (Pal. Soc.) p. 26, pi. ii. figs. 9-11, pi. iv. fig 6. 



Type. Dorsal shield ; unknown. 



The type species, the dorsal shield attaining a length of about 

 0'05. Median disc oblong, strongly arched from side to side, trun- 

 cated posteriorly, with a very small median spine ; rostrum very 

 short and broad ; lateral cornua extending from the orbits back- 



Fig. 17. 



Outline of dorsal shield of Cyathaspis, restored by Laukester. 

 c, cornua; d., median disc; o., orbit; r., rostral plate; s., dorsal spine. 



wards, broadest mesially, tapering behind, and not projecting beyond 

 the posterior margin of the disc. Superficial striae fine, those of the 

 rostrum transverse, the others longitudinal, and those of the disc 

 partially subdivided into groups by irregular longitudinal costae. 



Form. § Loc. Upper Ludlow and Downton Sandstone : Here- 

 fordshire. 



45939. Small slab of Downton Sandstone, with casts of four im- 

 perfect shields, one figured by Lankester, op. cit. pi. iv. 

 fig. 6 ; Bradnor Hill, Kington. Lighibody Bequest. 



P. 684, P. 683. Ferruginous fossil shield, showing the coarse longi- 

 tudinal costae of the disc with intervening fine striae ; also 

 a cast of the inner aspect of part of a similar specimen 

 displaying some of the supposed branchial excavations and 

 the pineal pit; Downton Sandstone, Kington. 



Egerton Coll. 



