GENEEA AND aEOUPS OF THE ECHIlSrOIDEA. 183 



The periproct is narrow bottle-shaped at the upper part, in a long, 

 narrow, posterior groov^e, which is shallowest and broadest just 

 above a tongue-shaped slope at the margin of the test ; irregular 

 minute grooves on the sides of the groove. Spines small, closely, 

 longitudinally striated. 



Fossil. Cretaceous : Europe, Asia (S. Hindustan), "W. Africa. 



Grenus Echinanthus, Breynius, 1732, ScJied. de Echinis, p. 53 

 (pars). Besor, Synopsis, 1858, p. 291. (See p. 149 of this 

 Eevision.) 



Syn. Parapygus, Pomel, 1883. 



Test moderate and small, thin, ovoid and broadest posteriorly 

 at the tumid undulating margin, low, convex above, concave 

 actinally. 



Apical system with four perforated basal plates ; madreporite 

 small, slightly excentric in front, but separating the postero- 

 lateral basals and also the radials. 



Ambulacra unequal, petaloid, varying in the amount of closure, 

 usually short, but may be long, continued simply over the margin, 

 and developing into phyllodes at the peristome ; the poriferous 

 zones may be unequal. Interradia well developed. 



Peristome excentric in front, less so than the apical system ; a 

 pentagonal floscelle well developed, and the bourrelets especially. 

 Periproct oval, marginal or suprainarginal, placed at the top of a 

 more or less developed groove. Ornamentation of very small 

 tubercles and granules, close, largest actinally. 



Fossil. Cretaceous : Europe. Eocene : Europe, Asia, Africa 

 (Egypt). 



FcJiinanthus Mortonis, Mich, sp., is the Hardouinia Mortoni 

 of Haime ; I agree with Desor (Synopsis, p. 295) in not recog- 

 nizing Haime's genus ; but I consider it is a good subgenus. 



Subgenus Hardouinia, J. Haime, 1853, d'Archiac Sf Haime, 

 Anim. foss. de Vlnde, p. 214. 



Test conical, as broad as long. Petals broad, pointed, reaching 

 rather more than halfway to the margin. 



Peristome nearly central, with a very well-developed floscelle. 

 Periproct large, midway between the margin and the summit, in 

 a groove. 



Fossil. Eocene : Europe. Tertiary : Mississippi, U.S. America. 



