284 



ECHINODEEMATA— ECHINOZOA 



PHYLUM IV 



sutures, and small, perforate and crenulate tubei'cles. 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. 



Conulus Leske (Galerites Lam.). Amh flush or slightly raised, apetalous, 

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



Fig. 398, 

 Conoclypeus conoidcus (Goldf.). Eocene ; Kressenberg, Bavaria (2/3 natural size). 



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

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



Lanieria Duncan. Cretaceous or Eocene ; Cuba. 



Conodypeus Ag. (Figs. 369, E ; 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. 



J\aiiiily 2. Pygasteridae Gregory. 

 Perignathic girdle <ipparentlij consisting of auricles only. 

 Holecfypus Desor (Figs. 369, B ; 399). Amh narrow, straight, widest at 



I'lc. 399. 



A.H, IIolectypnsoryir.alngSc]\\oth. Upper .lura; Streitlx^rs, I'Yancoiiia. '', />, 7/. '^cyiros!;.'-' (TiPske). Middle 

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



