54 BRITISH PALEOZOIC PIIYLLOCARIDA. 



22. Ceeatiocaeis gobiiformis, T. B. J. .5- //. W., 1885. PI. VIII, figs. 6 a, 6 h, 



11 a, 11 b. 



1885. Ceeatiocaeis qobiifoemis, T. R. J. ^ R. W. Third Eeport Pal. Phyl]., 



Brit. Assoc, p. 347 ; 

 Geol.Mag., 1885,p. 462. 



1886. — — _ Fourth Eeport, p. 232 ; 



Geol. Mag., 1886, p. 459. 



A form closely approaching G. solenoides in shape, but smaller, less acute in 

 front, usually more vertically truncate behind, and much more convex on the 

 ventral border, accompanies C. solenoides in the Upper-Ludlow sandstone of 

 Benson Knot. One of the specimens marked 6/8, Cambridge Mus.,is 27 mm. long 

 by 9 mm. high; one in the Brit. Mus., No. 44342, is 30x]0 mm. The valves 

 seem to have been smooth. They are somewhat boat-shaped in outline, and 

 distantly resemble a deep-bodied, blunt-headed little fish, such as a gudgeon, 

 without its tail ; convex ; straight or nearly so in the back, strongly curved below ; 

 rounded to a very blunt angle in front, obliquely truncate behind. It is possible 

 that this may be a varietal or sexual form of C. solenoides, but it seems to be 

 sufficiently well separated from its ally to require a distinctive name, so we refer 



to it as C. GOBIIFORMIS. 



This is near C solenoides, but is relatively broader (higher) and shorter ; the 

 ventral margin is much more convex, and the front end blunter. 



PI. VIII, figs. 6 a, 6 h. Brit. Mus., one of the specimens marked No. 44342. 

 In dark-grey, micaceous, fine-grained sandstone, slightly calcareous ; from Benson 

 Knot. 



PI. VIII, figs. 11 a, 11 I, 11 c. Cambridge Museum / 142. In dark-grey 

 sandstone, calcareous ; from Benson Knot. In this small valve (10x4 mm.), the 

 ventral border is still somewhat embedded in the matrix ; and there are three 

 small adventitious accretions on the apparently smooth surface. 



