124 Dr. T. Wrisrht on Fossil Echinoderms 



'O 



sica, which has enabled us to identify the Maltese Urchin, and 

 make out the preceding description, the first given of this pretty 

 form. 



Echinolampas Richardi, Desmarest. 



Syn. Scutum ovatum Issi/aviense, Klein, Echinodermatum, tab. 20. 



fig.«,i,§ 77. p. 29 (?). 

 Clypeaster Richardi^ Desm. Diet. Sc. Nat. t. liv. tab. 5. p. 12, spec. 



ined. in litt. ; Grateloup, Mem. Echid. Foss. tab. I. fig. 8 a, 6, 



p. 44. 

 Echinolampas Richardi, Desmoulins, Etudes sur les Echinides, p. 342. 



no. 4. 

 Echinolampas Laurillardiy Agassiz and Desor, Ann. Sc. Nat. t. vii. 



p. 165. — Scilla, Corp. Mar. tab. 11, top figure, showing the base 



only. 



Test oblong, produced posteriorly, rounded before, flattened 

 laterally, caudate posteriorly ; dorsal surface convex, elevated ; 

 base concave ; mouth central ; anus inframarginal, lodged in 

 a caudal process of the interambulacrum ; ambulacral areas 

 narrow, with contracted poriferous zones. 



Dimensions. — Antero-posterior diameter I-^-q inch, transverse 

 diameter 1/q inch, height ^Jths of an inch. 



Description, — The specimen before us is so much injured on 

 the dorsal surface, that we are unable to give a detailed descrip- 

 tion of this species, which appears to be not uncommon at Malta. 

 The ambulacral areas are narrow; the pores lie in contracted 

 zones, and the pairs are unconnected by sulci ; the avenues ex- 

 tend more than half-way down the sides of the test ; the dorsal 

 surface is elevated and convex, rounded before, and sloping gra- 

 dually from the vertex to the posterior border ; the apical disc 

 is very excentrical, and placed near the anterior border; the cir- 

 cumference of the test is of an irregular oblong figure, round 

 before, flattened on the sides, and produced behind : the base is 

 undulated by the elevations of the interambulacra and the de- 

 pressions of the ambulacral areas ; the single interambulacrum 

 is prolonged backwards, and is truncated at the sides and at the 

 posterior border, which gives it a caudate form. The mouth 

 is nearly central, and is sunk in a deep depression; it is 

 transversely oblong, and is surrounded by five oral lobes, 

 having five petaloidal depressions of the ambulacral areas, with 

 three pairs of pores in each petal between them; the anus is 

 larger than the mouth-opening, and is situated at the inframar- 

 ginal border of the caudate process of the interambulacrum ; it 

 has a transversely oblong form, and is more convex before than 

 behind. The Urchin figured by Grateloup is much larger than 

 the Maltese specimens that have come under our notice ; but 



