ECHINODERMATA—ECHINOIDEA SUB-BRANCH III 
bo 
bo 
ie 
(a) Cidaris, s. str. IAmb coronal plates five to eight. dmb more or less undulating ; pairs 
of pores rather close, separated by a nodule or ridge. Primary tubercles perforated and 
crenulated. 
(b) Rhabdocidaris, Desor (Fig. 359), Test large and swollen. Poriferous zones wider than 

Fia. 356. 
Cidaris coronata, Goldf. Upper Jura (y); Hossingen, Wurtemberg. A, Dorsal aspect of test with perfectly 
preserved apical system. JB, Profile. C, Portion of Amb, magnified. D, Partially restored view with spines 
attached. 
in Cidaris, the two pores of a pair being distant and conjugated. -d4mbd in general straight. 
Tubercles large, strongly crenulated, and more numerous than in Cidaris. Spines very stout, 

Fig. 358. 

Cidarid spines. A, 
C. alata, Ag. 3B, C. 
Fig. 357 dorsata, Braun. Trias ; 
rae St. Cassian, Tyrol. C, 
Cidaris tribuloides, Lam. Recent. Enlarged view of peristome C. florigemma, Phill. 
showing plated covering. Coral Rag; Wiltshire. 
some cylindrical or prismatic, often spiniferous. Chiefly Jura and Cretaceous ; less common in 
Tertiary and Recent. 

