CLASS I 



ECHINOIDEA 



291 



transversely elongate, and in a long groove. Periproct high up, usually in a 

 groove along the median line of the posterior lAmh. Upper Jura. 



P'ljgurus Ag. (Fig. 410). Test large, angular, rounded or cordiform in 

 marginal contour ; depressed or rather tall and sub-conical dorsally. Amh 



V .-->..■ S-.'.'° 



,".•-?>-■';' 



"^^^M- 





\\-^'^^'^ -^^M.^?:^ *^..i,i-:^ ■'*/-> "^ 







-■■^■■i-^ 



■.-■^.-^ ■'■i'. 



% 





;.'; - ~ ''// '^ /<'>'/»•./• <- '.' '•. »a . I .^ 





Fio. 411. 

 Echinolampas Ideini Go\di. Oligocene ; Doberg, near BUnde. i/i. 



flush dorsally, unequal, wide ; the petaloid parts contracting but not closing 

 marginally, and expanding again actinally, where the Amh are grooved. Peri- 

 proct infra-marginal, pyriform or ovoid, in a special area, or rostrum, close to 

 the posterior edge of the test. Upper Jura and Cretaceous. 



Echinolam'pas Gray (Fig. 411). Test variable in size and shape, more 

 or less ovoid or circular at the tumid ^ c 



marginal outline ; tall and conical or 

 depressed dorsally. Amh petaloid for 

 a variable distance; pores of the petals 

 differing in shape, conjugated and con- 

 tinued beyond in simple series. Peri- 

 stome slightly in front, or sometimes 

 central. Periproct transversely ellip- 

 tical, infra-marginal. Widespread in 

 Tertiary and Kecent. 



Conolampas and N'eolampas A. Ag. 

 Recent. Plesiolamixis Duncan and 

 Sladen. Eocene. Palaeolampas Bell. 

 Upper Cretaceous to Recent. 



Family 3. Collyritidae d'Orbigny 

 (^Dysasterinae Gray). 



Apical system disconnected, either 

 elongate or suh- compact. Ambulacra 

 similar ; hivium widely separated from Pi,;. 412, 



the trivium ; floSCelle absent. Jura to CullyriteselUptka'DeHm. Callovian ; Mamers, Sarthe. 

 p, ^ , .1, B, Test in profile and from above, i/i- t', Apical 



UretaceOUS. system, enlarged. 



