286 



ECHINODEEMATA— ECHINOZOA 



PHYLUM IV 



re-entering angles. Petals long, broad, tumid ; pores wide apart, unequal, 

 conjugated. Periproct near or at the edge. Internal structure not forming 



a double wall covering the 

 Amh. This genus includes 

 some of the largest known 

 Echinoids. Eecent species 

 are littoral, or shallow- 

 water inhabitants. Tertiary 

 and Recent. 



Anomalantlms Bell. Ee- 

 cent. Lagannm Gray. Be- 

 longs propei'ly to a separate 

 family or subfamily. Ter- 

 tiary and Eecent. 



Family 2. Fibulariidae 

 Gray. 



Test small, with nidi- 

 menlary, widely open, few- 

 pored petals. Interamhvlacra 

 small, with a single apical and a single peristomal plate. Ambulacra limited 

 actinally on the interior of the test by low vertical partitions at their sides, radiating 



Clypeaster aegyptlcus Mich. Pliocene ; Gizeli, near Cairo. Fragment, 

 showing internal calcareous deposits, au, Auricles. 



Clypeaster grandiflorus Bronn. 



Fill. 402. 

 Miocene ; Boutonnet, near Montpellier. i/o natural size (after Desor). 



toward the peristome. Perignathic p>'>'ocesses broad, low, situated on each inter- 

 ambulacrum. Periproct usually actinal. Cretaceous to Eecent. 



Echinocyamus Leske (Fig. 403). Test thick, depressed, pyriform or sub- 

 circular in outline, concave actinally. Amb broader than the lAmb, short 



