494 jff. Woodward — New British Fossil Crustacea. 



middle of the carapace for about one-tliird of its breadth, then 

 passing in an oblique direction outwards and forwards, reaching the 

 lateral margin in a deep and broad depression behind the orbits ; 

 gastric region strongly ridged, having one large and -very prominent 

 median tubercle midway between the rostrum and cervical furrow 

 and two small lateral ones ; hepatic region marked by one central 

 tubercle, margin indented; cardiac region with a strong median 

 ridge, ornamented with numerous small tubercles along its most 

 elevated part ; branchial region ornamented down the centre by a 

 raised line marked by from four to five tubercles, border slightly 

 tuberculated ; basal joints of antennules small ; those of external 

 antennas broad and flattened, as in other genera of this family ; 

 posterior border of carapace deeply arched ; abdomen rounded, 

 raised along the centre, epimera rounded and deeply grooved within 

 the margin, surface finely granulated ; segments decreasing in 

 breadth from the second to the fifth (sixth and seventh segments 

 wanting). Portions of the external maxillipeds only preserved ; the 

 three first joints of nearly all the five pairs of ambulatory limbs 

 (coxopodites) have been preserved ; near the base of the third pair 

 may be seen the apertures of the efferent ducts of the ovaries; 

 sternum somewhat deeply corrugated transversely, and relieved by 

 five pairs of rather prominent tubercles, corresponding to the five 

 thoracic somites which bear the five pairs of coxopodites or walking 

 feet, from the bases of which latter they take their rise ; the first 

 pair of tubercles are very minute, and closely approximate to each 

 other on the median line, each succeeding pair of tubercles increases 

 in size and in distance apart just as the sternum increases in width 

 from its anterior to its posterior border ; they present the appearance 

 of a double row of mammce. The feet decrease in size from before 

 backwards and are somewhat flattened in section, as in the recent 

 Scyllaridce. 



Dimensions : — Length of carapace along the median line, 10 lines ; 

 length along the branchial and hepatic region, 1 inch ; breadth at 

 widest part, 10 lines ; breadth of anterior border of carapace, 6 lines; 

 breadth of posterior border, 8 lines ; thickness from sternum to 

 dorsal ridge, 7 lines. 



Scyllaridia Bellii is readily distinguished from S. Koenigii, not only 

 by its size, its more strongly-marked carapace, — rising to a very 

 elevated ridge along the centre (see Fig. 2), — its more expanded 

 branchial region and deeply-curved posterior border ; but also in 

 the relative openness of the orbital fossa in the former (in this 

 respect offering an approach to Thenus, a genus allied to Scyllarus) as 

 compared with the more perfectly inclosed orbit in the latter. Nor 

 do I see any reason to doubt that the specimen here described is an 

 adult individual. So far as its remains have been preserved to us, 

 Scyllaridia Bellii is one of the most beautiful macrouran crustaceans 

 found fossil, and when examined with a pocket-lens its minute de- 

 tails of structure are seen to be remarkably well preserved. It was 

 obtained from the London-clay of Sheppy, and is now in the British 

 Museum Collection. 



