XIV 



EXPLANATION OF THE PLATES. 



FIG. 7. The suture of a portion of the lateral grove 

 uniting with the above, in which the trans- 

 verse pieces are concave. 



8. Suture of the intermediate grove divided at 



the ridge (Fig. 3. b.). Teeth obtusan- 

 gular. 



9. A circular space round the mouth, co- 



vered with little oblong scales. In the 

 centre is the mouth with its five converg- 

 ing teeth. 



10. Outside of one of the five pyramidal jaws, 



in which the teeth are planted. 

 a. The jaw. b. The tooth. 



11. Inside of ditto : a. the jaw, consisting in- 



ternally of two triangular transversely 

 furrowed, and probably molary plates. 



12. A little bristle, terminating in a knob with 



three awns, planted amongst the spines 

 on the shell, and, according to Cuvier, 1 

 a species of Polype (Pedicellaria). 



13. Another Pedicellaria? expanded like a 



tripetalous blossom. 



14. One of the spines of Echinus esculentus. 



Page 



>208 211 



PLATE III. B. CRINOIDEANS. 



FIG. 1. Pentacrinus Asteria vol. ii. 13 



2. Portion of ditto, exhibiting the suckers on the 



under side of the fingers 12 



PLATE IV. TUNICARIES. 



FIG. 1. Cinthia Momus 230 



2. Salpa cyanogastra 223 



3. Pyrysoma giganteum 227 



4. Cephalitis Eowdichii 222 



5. Clavellina borealis. . 230 



1 Regn. An. ii!. 297. 



