from the Lias and Oolites, 315 



form of Pedina from the Pea-grit of Crickley Hill, and have seen 

 fragments of its test in the same bed at Leckhampton, but 

 never in any other locality. 



We dedicate this species to our friend T. Barwick L. Baker, 

 Esq., of Hardwicke Court, the President of the Cotteswold Natu- 

 ralists^ Club, for the warm interest he takes in the progress of 

 the Palaeontology of Gloucestershire. 



Pedina Etheridgii, Wright. PI. XI. fig. 5, a-c. 



Test circular, depressed ; ambulacral areas with from six to eight 

 small perforate tubercles at their base, and a double row of 

 small granules on their upper surface; the interambulacral 

 areas with primary tubercles only, the areolas of which are 

 surrounded with regular circles of granules ; pedal pores not 

 numerous, arranged in nearly a single file with a slight ele- 

 vation between the two pores of each pair ; apical disc large ; 

 ovarial plates leaf-like ; mouth-opening small. 



Height /oths of an inch, transverse diameter ^gths of an inch. 



Description, — This pretty little Urchin has a circular outline 

 in the young state, which in larger specimens inclines towards a 

 pentagonal form ; the base is flattened, and the upper surface of 

 the test is much depressed. The ambulacral areas are narrow, 

 and have from six to eight small perforated tubercles at their 

 base, and a double row of from twelve to fourteen minute imper- 

 forate granules in each row on their upper surface, which in 

 figure and size resemble those covering the other parts of the 

 test ; between the pedal pores of each pair is a small elevation ; 

 these collectively form a prominent moniliform line which ex- 

 tends from the margin of the disc to the mouth-opening; the 

 pores are disposed in nearly a single file, and do not form the 

 triple oblique pairs which we observe in the larger Pedina. The 

 interambulacral areas are about twice the width of the ambu- 

 lacra ; the rows of primary tubercles occupying the centre of the 

 plates have seven tubercles in each row, they are small in size 

 and are rendered prominent from being raised upon uncrenu- 

 lated mammillary eminences, the bases of which are sharply de- 

 fined and surrounded by complete circles of moderately sized and 

 regularly arranged granules; the regular disposition of these 

 granulations gives an air of decoration to this little species not 

 observed among other congeneric forms ; the entire absence of 

 secondary tubercles from the areas renders the decoration more 

 complete. The apical disc is large ; the ovarial plates are widely 

 rhomboidal, the oculars are small and heart-shaped, and the sur- 

 face of both is covered with minute granules nearly as large as 

 those which adorn the other parts of the test. The madrepori- 



