284 



ECHINODERMATA— ECHINOZOA 



PHYLÜM IV 



sutures, and small, perforate and crenulate tubercles. Plates within the 

 actinal surface with radiating ribs, ten in all, extending as far as the peri- 

 stome ; appearing on casts as deep depressions. Periproct small, infra- 

 marginal. Cretaceous. 



Conuhis Leske (Galerites Lam.). Amh flush or sligTitly raised, apetalous, 

 straight ; some of the plates Compound. Peristome sunken, slightly decagonal. 



Fio. 398. 

 Conoclypeus conoideus (Goldf.). Eoceiie ; Kresseiiberg, Bavaria (^^ natural size). 



symmetrical. Perignathic girdle indicated by a thickening of the lAmb as a 

 low false ridge. Abundant in the Lower and Middle Cretaceous. 



Lanieria Duncan. Cretaceous or Eocene ; Cuba. 



Conoclypeus Ag. (Figs. 369, B ; 398). Test large, thick ; conical or vaulted 

 dorsally, flat actinally. Amb long, open, with broad poriferous areas nearly to 

 ambitus, narrowing thence to peristome. Pores wide apart and in pairs where 

 the areas are broad ; the pairs separated by costae. Pores continued in single 

 series over the ambitus as far as the central, pentagonal peristome. Periproct 

 infra-marginal, oval (?), Cretaceous and Eocene ; Europe. 



Family 2. Pygasteridae Gregory. 

 Perignathic girdle ^pparently consisting of aurides only. 

 Holeäypus Desor (Figs. 369, B ; 399). Ar)ih narrow, straight, widest at 



Fig. 399. 



A,B, Holectypusorificatua^c\\\oi\\. Upper Jura ; Streitber<^, Franconia. (', ]), JL depresmf: (Jjeske). Mlddh 

 Jura ; France. Apical System and ventral surface (after Cotteau). 



