GENERA Al«fD GROUPS 01? THE ECHmOIDEA. 195 



Peristome slightly excentric in front, small, pentagonal, broader 

 than long, with bourreleta and phyllodes feebly but definitely 

 developed. Periproct elongated transversely, submarginal. 



Fossil. Upper Cretaceous: Franceo Tertiary: Europe*. 



Genus Microlampas, Ootteau, 1887, Bull. Soc. Zool. de France, 

 p. 637, pi. X. figs. 10-13, 



Test small, circular, tumid, subcorneal dorsally, flat, subpulvi- 

 nate actinally. 



Apical system central, the madreporite projecting centrally, 

 with small radial plates. 



Ambulacra becoming wider towards the ambitus, subpetaloid, 

 open at their ambital extremity ; poriferous zones composed of 

 small unequal pores, appearing to be united by a groove, the 

 outer pairs more elongate tlian the inner. At a considerable 

 distance from the margin of the test the pairs cease, and a single 

 row of pores is continued to the peristome. 



Interradia more or less keeled close to the apex, the orna- 

 mentation similar to that o£ the ambulacra, not abuiidant, of 

 small crenulate and perforate primary tubercles, largest at the 

 ambitus and actinally. 



Peristome deeply seated, pentagonal, with a slight fl.oscelle. 

 Periproct rounded in outline, flush, iuframarginal. 

 . Fossil. Eocene : Europe. 



There is but one species, and it is small, but the affinities with 

 PulcEolam^as and Conolampas are interesting. 



Genus Neolampas, A. Agassiz, 1869, Bull. Mus. Comp. Zool. i. 

 p. 271 ; 1872-4, Bevision of FcMni, p. 340. Wyville 

 Thomson, 1874, Phil, Trans, vol. clxiv. p. 745. 

 Test small, thin, depressed, pyriform, arched above, truncated 

 obliquely behind and rostrated, concave actinally. 



Apical system in front of the highest point of the test, with 

 four basal plates, three o£ which are perforated, and the madre- 

 porite is in the right anterior, and separating the basals 1 and 4 

 more or less. 



* M. Pomel, 1883, Theses, p. 62, has mistaken the meaning of Palceolampas, 

 which he considers to be a subgenus of Echinolam'pas. He places in it Echino- 

 lampas Hellei, Val. ; but this recent form has ambulacra differing from those of 

 PalcBolampas, and it is a true Echinolampas. 



13* . 



