146 



\acra, brissi, and those wliich have five, spatangi ; the ge- 

 neral form and characters of both of which are represented 

 in PI. ii. fig. 13, 11. 



Srissus, ( Ovmn-marinum ) , PI. ii. fig. 13 ; SpatanguSy 

 (Cor. mariniimj, fig. 11. 



* With four ambulacra (brissi,) 



Sp. 1. Spatangus pectoralis. — Ovato-elliptical, depressed, 

 large ; four ambulacra, with the interstices elegantly granu- 

 lated ; the assulse elongated at the margin. Recent. — Seba, 

 Mus. iii. Tab. xiv. fig. 5, 6. 



2. S. ventricosus. — Ovate, inflated, obsoletely assulated ; 

 with four oblong canaliculated ambulacra; the larger tu- 

 bercles placed in zig-zag. . Recent. 



Brissus ventricosus. — Leske ap. Klein, Tab. xxvi. fig. A. 

 An. Scill. Corp. Marin. Tab. iv. fig. 1, 2. 



3. S. purpureiis. — Cordated; with four smooth lance- 

 olate ambulacra ; the larger tubercles placed in zig-zag. 

 Recent and fossil. 



Spatangus purpureus. — Leske ap. Klein, Tab. xliii. 

 fig. 3-5 ; Tab. xlv. fig. 3. Scill. Corp. Marin. Tab. ii. 

 No. 1. fig. 1. 



4. >iS'. ovatus. — Ovate ; semicylindrical ; depressed back- 

 wards, with four excavated canaliculated ambulacra, the 

 fore ones oblique. 



Spatangus brissus unicolor. — Leske ap. Klein, Tab. xxvi. 

 fig. B. C. Recent. 



3. S. carinatus. — Ovate, inflated, and a little turgid at 

 the sides ; ambulacra four, the fore ones transversely diva- 

 ricated ; the dorsal area carinated backwards, and obtusely 

 projecting. Recent. 



Spatangus brissus, late carinatus. — Leske ap. Klein, 

 Tab. xlviii. fig. 4. 5. 



6. *S'. columbaris. — Oval ; vertex depressed ; with four 

 shortish ambulacra, the hinder ones straight. Recent. — 

 Seba. Mus. iii. Tab. x. fig. 19. 



