122 GLYPHOCYPHUS 



EcuiNOPSis LATIPORA, Jgassiz et Desof. Ibid., p. 351, 1 84G. 



— CONTEXTA, Agassiz et Desor. Ibid. 



— DEPRESSA, Agassiz et Besor. Ibid. 



— CONTEXTA, Bronn. Index Palseontologiciis, p. 447, 1818. 



— DEPRESSA, Bronn. Ibid. 



— LATIPORA, Bronn. Ibid. 



— PUSiLL.i, Bronn. Ibid. 



Arbacia RADIATA, Bronti. Ibid., p. 91, 1848. 



TEMNOPLEUKUSPDLCHELLUSjiSor/jrne^. Ours. fossiles du Dep. de I'Eure, p. 31, 1850. 

 Glyptious Koninckii, Forbes. la Di.xon's Geology of Sussex, p. 340, tab. xxt, 



fig. 30, 1850. 

 EcHiNOPSis PDsiLLA, Forbes. In Dixon, ibid., tab. xxv, fig. 31, 1850. 



— — Giebel. Deutschlaiids Petrefacteu, p. 320, 1852. 

 Glyphocyphus pulciiellus, d'Archiac et Jules Haime. Descript. Nummilites de I'liide, 



p. 202, 1854. 

 Morris. Catal. of Brit. Fossils, 2nd. ed., p. 78, 1854. 

 Tiaite de Paleontol., 2e ed., p. 242, 1846. 

 Ibid. 

 Ibid. 

 Ibid. 

 Ibid. 



Synopsis des fichinides fossiles, p. 103, tab. xvii, 

 figs. 1—3, 1856. 



— — Cotteau et Triger. Eciiinides du de'p. de la Sartlie, p. 185, 

 pi. xxviii, figs. 7 — 12, 1859. 



— — Dujardin et Hupe. Hist. uat. des Echinod., p. 513, 1862. 

 Temnopleurus pulchellus, CojMarerf. Geol. et Pal. de la prov. de Constaiitine, p. 294, 



1863. 

 GLYPHOCYPnus radiatus, Cotteau. Paleont. Fi-an9., Ter. Cretace', t. vii, p. 535, 



pi. 1127, 1128, 1863. 



Test small, circular, inflated, subglobular, rounded at the border and concave at the 

 base ; ambulacra very narrow, with two rows of tubercles, alternate, irregular. Poriferous 

 zones narrow, straight ; simple pores in single oblique pairs. Inter-ambulacra with two 

 rows of small tubercles, areolae radiated, plates grooved at the lower border ; apical disc 

 solid, forming a narrow, elongated, subpentagonal ring, having the genital and ocular 

 plates almost of equal length ; oculars finely granulated ; vent large, oblong. 



Dimensions. — Height five twentieths of an inch ; transverse diameter eight twentieths 

 of an inch. 



Description. — This small Urchin has been a great puzzle to Palaeontologists, as proved 

 by the long Hst of synonyms given above. The test is circular, inflated, and subglobular; 

 rounded at the sides, and concave towards the base (figs. 1 a, b). The ambulacral areas 

 (fig. 2 e), about half the width of the inter-ambulacral, have two rows of smafl tubercles, which 

 form an alternate series on each side of the area ; they are largest at the ambitus, smaller 



