﻿184 



OSTEOSTRACI. 



of relatively large tubercles surrounded by groups of small tubercles ; 

 margin of the shield with a close series of well-developed spinelets. 

 The outline-restoration of the shield of this species, published by 

 Lankester (fig. 23), appears to be too acute anteriorly, while the 

 cornua seem to be too straight, long, and narrow. The marginal 



Fig. 23. 



Cephalaspis pagei, Lank. — Outline of shield, and a portion of its superficial 

 ornament much magnified (A). After Lankester. 



asperities are shown in all the specimens mentioned below, thus 

 confirming Lankester's suspicion that Eucephalaspis asper might be 

 only the adult of the present form. 



Form. <$f Loc. Lower Old Eed Sandstone : Forfarshire. 



P. 122-124. Three typical specimens, showing portions of the head 

 and trunk, the first two being in counterpart ; Turin Hill, 

 Forfar. Purchased, 1880. 



50115. Half of anterior shield, and imperfect lateral aspect of trunk ; 

 in micaceous sandstone from Forfarshire. 



Purchased, 1879. 



P. 670. Head and trunk about 0-16 in length ; Turin Hill. The 

 anterior portion of the shield exhibits traces of the charac- 

 teristic ornament, and the dentate margin is distinct. The 

 fine rhomboidal squamation of the heterocercal tail is well 

 preserved ; and the dorsal and caudal fins occur as granu- 

 lated membranous expansions. Egerton Coll. 



P. 125. Imperfect head and trunk of a large individual, in counter- 

 part ; Turin Hill. This specimen precisely resembles the 

 typical C. asper. Purchased, 1880. 



