﻿Tol. 66.] THE CAMBKIAX ROCKS OF COMLEY. 31 



Agraulcs, Corda. 

 Subgenus Strenuella, Matthew. 



In 1886 Mr. Matthew 1 called attention to the divergence of 

 .A. strenuus, Bill., from the type of Corda's genus, and proposed 

 the name of Strenuella for a subgenus, of which Billings's species 

 would form the type ; and in 1887 - he referred (but with a 

 note of doubt) his species A. (Strenuella?) hatliana to the same 

 subgenus. 



A form occurs at Comley which seems closely related to 

 A. strenuus, var. nasutus, Walcott, and should come under the 

 same subgenus. It has some points of resemblance with Anomo- 

 care, Angelin, but would seem to have a wider head-shield than 

 the type of the genus, and a small pygidium very different from 

 the rounded pygidia described and figured by Angelin. It appears 

 to me that Strenuella might well be adopted as the name for a 

 genus intermediate between Agraulos and Anomocare : but with- 

 out access to specimens of Agraulos strenuus, Bill, (which should 

 form the type species), I cannot sketch out a generic diagnosis. 



Ageaeeos (Steexeella) salopiensis, sp. nov. (PL IV, figs. 1-9.) 



E. S. Cobbold, Anomocare. cf. Agraulos strenuus, var. nasutus, Wale, Rep. 

 Brit. Assoc. 1908 (Dublin) 1909, p. 236. 



Fragments of this species occur in abundance in one band of the 

 grey limestone of Comley ; but they are difficult of extraction, 

 owing to the strong relief of the features. 



I have portions of twelve or more individual cranidia in my 

 collection, the most complete, though not the largest, of which 

 [161] is figured. 



The fragments of this species are intimately mixed in the rock 

 with those of another of about the same size, and the correlations 

 made below, of pygidium, thoracic segments, and free cheeks with 

 these cranidia, are necessarily matters of inference. 



Ceanieiem : Size. — Length (exclusive of the nuchal spine) = 

 from 7 to 10 millimetres ; the width across the eye-lobes is about 

 half as much again. 



General form. — Broadly subquadrangular, with a very widely 

 curved front and a somewhat sinuous posterior border, from which 

 the long nuchal spine projects backwards. 



Convexity. — The glabella is strongly convex, the fixed cheeks 

 are more or less horizontal, and the sides of the head- shield dip 

 steeply down. The convexity works out at about \. 



Glabella.— Almost semicircular in convexity ; somewhat para- 

 bolic in outline ; width, about a third of that of the cranidium ; 

 length, about three quarters of that of the shield without the nuchal 



1 Trans. Roy. Soc. Can. vol. iv, sect. ir. pp. 151, 154. 



2 Ibid. vol. v. sect, iv, p. 132. 



