from the Lias and Oolites. 19 



greater size and uniform perforation of the miliary tubercles, but 

 above all by the form and structure of the primary spines. 

 Having ascertained that our conjecture * relative to the spines 

 of C. Fowleri is correct, from having seen a specimen recently 

 found with some spines attached to it, we can speak positively 

 upon this point. 



Locality and stratigraphical range. Found by Mr. G. E. 

 Gavey, C.E., in the upper shale beds of the Lower Lias at 

 Mickleton Tunnel near Chipping Campden. It was associated 

 with Pentacrinus Goldfussii, Wright, Ophioderma Gaveyi, Wright, 

 Uraster Gaveyi, Forbes, and Ammonites planicosta, Sow. 



History. Isolated plates of this species have been found in 

 beds of the same geological horizon in other localities of the 

 county of Gloucester, but the specimen before us is the only 

 one from which the anatomy of the Urchin could be made out. 

 We dedicate this species to Prof. Milne-Edwards, of the Museum 

 of Natural History at the Jardin des Plantes, Paris, as a tribute 

 of gratitude for the pleasure and profit derived from the study of 

 his admirable monograph on British Fossil Corals. 



Cidaris Bouchardii, Wright. PI. I. fig. 2, a-c. 



Test circular, depressed ; ambulacral areas narrow and flexuous ; 

 interambulacral areas with two rows of primary tubercles, 5-6 

 in each row ; the areolas of the small mammillary eminences 

 deeply excavated, and surrounded by an elevated ridge, on 

 which a distinct circle of granules for each areolar space is 



Dimensions of the largest specimen. Height Jths of an inch, 

 transverse diameter 1 inch and /^ths. 



Dimensions of a moderate-sized specimen. Height J^ths of 

 an inch, transverse diameter 1 inch and ^jths. 



Description. It was for some time doubted whether the young 

 forms of this Urchin were not the C. elegans, Goldf., but a com- 

 parison of several individuals of our fossil with a typical spe- 

 cimen of Goldfuss's species, kindly sent us by our friend Dr. 

 Roemer of Bonn, which he had identified with the original 

 C. elegans in the Bonn Museum now under his care, has con- 

 vinced us of their distinctness. The test of our Urchin is 

 circular and much depressed from the great flattening of both 

 poles ; the ambulacral areas are narrow and slightly flexuous, 

 and have two rows of small marginal granules set nearly op- 

 posite to each other throughout the areas. The poriferous 

 avenues are much depressed, and the pairs of pedal pores are 



* Annals of Nat. Hist. Oct. 1851. 



c 2 



