140 



4. S. sexforis. — Orbicular, depressed, and as if trun- 

 cated ; with six oblong foramina; the vent near to the mouth. 

 — Leske ap. Klein, Tab. 1. fig. 3, 4. Recent. 



5. S. quinquefora. — Orbicular, depressed, and sub- 

 reniform ; with five oblong foramina ; the vent near to the 

 mouth. — Leske ap. Klein, Tab. xxi. fig. C. D. Recent. 



6. S. quadrifora. 



This appears to be only a variety of scutella emarginata, 

 in which only two of the three posterior foramina reach the 

 margin. It however differs in being somewhat subreniform. 



7. S. bifora. — Obtusely trigonal and depressed ; with 

 two oblong foramina at the posterior part ; the vent distant 

 from the mouth. 



Echinod. bis perforatus. — Leske ap. Klein, Tab xxi. fig. 

 A. B. Recent. 



8. S. bijissa. — Cordato-orbicular, depressed ; with two 

 slits on the wider side, and an intermediate, projecting lobe, 

 with an undulating margin. 



Echinus auritus. — Leske ap. Klein, p. 202. 



9. S, lenticidaris. — Orbicular, rather convex ; with five 

 short ambulacra with open apices ; the vent marginal. 

 Fossil. Grignon. 



10. S. orbicidaris. — Circular, and depressed towards the 

 margin ; the back rather convex in the centre ; ovato-acute 

 ambulacra ; the vent between the mouth and the margin. — 

 Leske ap. Klein, Tab. xlv. fig. 6, 7. Fossil. 



11. S. Jibularis. — Small, orbicular, depressed, and rather 

 thick, the margin rounded ; the vent between the mouth and 

 the margin. — Lang. lap. fig. Tab. xxxv. fig. ult. Fossil. 



12. S. placenta. 



This is the name applied by Lamarck to the echinus 

 which has been assumed above as the type of the genus 

 arachnius, 



13. S. parma. — Orbicular; the back rather convex; 

 with five subovate ambulacra, disjoined at the apices; and 



