Professor T. T. Oroom — New Trilohite from Malvern. 71 



dying out behind ; each pleura facetted in front, and marked by 

 fairly deep, straight grooves for the whole of their length, the 

 grooves being margined in front by a well-defined ridge ; at their 

 ends the pleurae suddenly bend sharply backwards and a little 

 downwards, and end in spines ; traces only of the first three 

 pairs of spines are seen, but those of the fourth segment are long 

 and extend for some distance behind the end of the pygidium. 

 Length of the thorax, 0"54 millimeter ; breadth, 1"08 millimeter. 



Fig. 1. — Aeanthopleurella Grindrodi, gen. et sp. nov., restored with the aid of the 

 specimens shown in Figs. 3 and 4. The spines at the ends of the pleurae 

 of the first three rings of the thorax require very careful illumination to 

 render them visible. 



Fig. 2. — Optical section of the tergum of the thorax of the specimen shown in Fig. 3. 



Pygidium semi-elliptical ; axis convex, conical, terminating at 

 a short distance in front of the hind margin, and showing only one 

 well-marked transverse constriction. Limbs tolerably flat, with 

 several ridges and grooves corresponding to those of the thoracic 

 pleurae, and extending as far as the raised marginal rims. Margin 

 probably entire. Anterior angles apparently rounded. Length 

 of pygidium, about 04 millimeter ; breadth, 0"83 millimeter. 



The specimen is partly enrolled ; this fact, together with its 

 convexity, has made it impossible to obtain good photographs of 

 the whole trilobite. The total length when unrolled would be 

 1-4: millimeter, or two-thirds of a line. 



