﻿C0CC0STE1DJ":. 



291 



Coccosteus minor, Miller. 



1858. Coccosteus minor, H. Miller, l Cruise of the Betsey,' etc. p. 396. 



1888. Coccosteus minor, R. II. Traquair, Geol. Mag. [3] vol. v. p. 511. 



1889. Coccosteus minor, R. H. Traquair, ibid. vol. vi. p. 8, pi. i. fig. 3. 



Type. Imperfect skeletons ; Edinburgh Museum. 



A very small species, attaining a maximum total length of about 

 0-1. Cranial shield broader than long; mandibular teeth very 

 slender and sharply pointed ; infra-orbital bar of maxillo-suborbital 

 bone relatively deep. Median dorsal plate about twice as long 

 as broad, somewhat arched from side to side, gradually tapering 

 in its posterior half into a long, blunt point ; anterior border slightly 

 excavated, and the granulations much finer along the mesial longi- 

 tudinal line of the shield than at its sides. Posterior ventro-lateral 

 plates twice as long as broad, produced ab each postero-lateral angle 

 into a short spine. Tuberculations numerous, of moderate size, never 

 confluent, and not arranged in definite lines. Unarmoured caudal 

 region about equal in length to the head and armoured portion of 

 the trunk. 



As remarked by Hugh Miller, the remains of individuals of this 

 species occur in groups, at first sight suggestive of their being shoals 

 of young. 



Form. § Loc. Lower Old Red Sandstone : Caithness and Orkney. 



42383. Three imperfect associated individuals ; Murkle Bay, Caith- 



ness. Peach Coll. 



42335. Remains of two or more individuals on one slab, showing 

 stout well-ossified neural and haemal arches of axial 

 skeleton ; Murkle Bay. Peach Coll. 



42384, 42387-89. Four small slabs with scattered dermal plates ; 



Murkle Bay. The second specimen exhibits a mandi- 

 bular bone with teeth. Peach Coll. 



42386. Imperfect median dorsal plate, ventral aspect ; Thurso. 



Peach Coll. 



P. 689. Slab with scattered dermal plates of several individuals, 

 probably of this species ; Orkney. Egerton Coll. 



P. 3221-a. Two slabs with scattered dermal plates ; Orkney. The 

 second specimen shows an imperfect median dorsal plate 

 exhibiting some of the characters stated in the diagnosis. 



Ennishillen ColL 



v2 



