Geol. Mag. 1908. 



Dec. V, Vol. V, PL XVII. 



New Chalk Crinoids from the '' Micraster cor-tesiudinariiim zone' of the 

 Upper Chalk, Seaford Head, Sussex ; from Dr. Arthur Rowe's 

 Collection. 



Fig. I.— Oral view of Roveacrmus alata (gen. & sp. nov.), restored, x 17. 

 „ 2. — Lateral view of 7?. alata. x 10. 

 „ 3. — Lateral view oi R. conntioiis. x 10, restored. 

 „ 4. — Oral view of R. conununis. x 14 (the interradial spines are 



broken off). 

 „ 5. — Aboral view of j'?. coininufiis (var. rugosa). x 16. 



r. radial wing ; ar. radial articular facet ; / ligament fossa ; ax. axial 

 canal ; t.s. interradial spine ; c. carina ; b. basal ; r.k. radial keel. 



