﻿PTEKASPIDJ3. 169 



1868), p. 33, pi. v. figs. 1, 2, 6, 10, 11 : Pteraspis, 



H. Mitchell, Geologist, vol. vii. (1864), p. 117, woodc. — 



Lower Old Red Sandstone ; Forfarshire. [Internal cast 



of shield; Dundee Museum.] 

 Pteraspis podolica, A. von Alth, loc. cit. p. 42, pi. i. figs. 5-10, 



pi. ii. fig. 1. — Upper Ludlow ; Zaleszczyki, Kriszczatek, 



and Dobrowlany, Galicia. [Shields, wanting rostrum, but 



with relatively large cornua, 

 Pteraspis rhenana, C. Schliiter, Sitzungsb. niederrhein. Ges., Bonn, 



1887, p. 125. — Lower Devonian ; near Bonn. [Portion 



of median disc ; University of Bonn.] 



The impression of the inner aspect of an imperfect median disc of 

 Pteraspis from the Upper Silurian (or Lower Devonian) of Galicia is 

 named " Pterichthys ? " by R. Kner, Haidinger's Naturw. Abhandl. 

 vol. i. (1847), p. 167, pi. v. fig. 3 : see also Scaphaspis kneri, p. 174. 



Genus PALJEASPIS, Claypole. 

 [Amer. Naturalist, vol. xviii. lo^i, p. 1224.] 



Syn. Holaspis, E. R. Lankester {non J. E. Gray, 1863), Geol. Mag. 

 vol. x. 1873, p. 242. 



Scaphaspis, E. R. Lankester, Rep. Brit. Assoc. 1864 (1865), 

 Trans. Sect. p. 58 (in part). 



Dorsal shield resembling that of Pteraspis in form, but apparently 

 consisting of a single plate and destitute of a median dorsal spine. 

 Orbits forming notches in the shield at the base of the rostrum, not 

 completely enclosed. 



This genus was first defined by Lankester under the preoccupied 

 name of Holaspis, and the type species is P. sericea. 



Palaeaspis sericea (Lankester). 



1873. Holaspis sericeus, E. R. Lankester, Geol. Mag. vol. x. pp. 241, 

 331, pi. x. and woodc. 



Type. Dorsal shield ; British Museum. 



Shield narrow and elongated, the rostral region sharply rounded 

 and much broader than long; lateral margins, when uncrushed, 

 apparently bulging outwards immediately behind the orbits, nearly 

 parallel in the hinder half ; posterior margin angulated mesially. 



Form. Sf Loc. Lower Old Red Sandstone (Cornstones) : Aberga- 

 venny, Monmouthshire. 



P. 4117. Type specimen described and figured by Lankester, loc. cit. 

 Presented by Dr. D. M. McCidlouyh, 1883. 



