ASTEEOIDEA. 



37 



Order 4. — Asteroidea. 



(Sea- Stars, Brittle Stars.) 



Char. — Body free, radiate ; integument hardened by calcare- 

 ous pieces, and more or less armed with spines ; no 

 dental apparatus. 



Asteriadce and Ophiuridce. — Fossil star-fishes, though less 

 common, have a wider range than their allies the fossil urchins, 

 being found amongst the earliest organic forms. Palceaster, 



Fig. 7. 

 Galeritidce ; Asteriadce ; Crinoidea. 



i. Pygaster semisulcatus, Ph.; Inf. Oolite, Cheltenham. 



2. Ananchytes ovatus, Lam. ; U. Chalk, Europe. 



3. Galerites albogalerus, Lam. ; U. Chalk, Kent. 



4. Scutella subrotunda ; Miocene, Malta. 



5. Lepidaster Grayi, Forbes ; U. Silurian, Dudley. 



6. Protaster Miltoni, Salter ; L. Ludlow rock, Salop. 



7. Comatula (Glenotremites), upper surface of body. 



8. Comatula (lower surface) ; Chalk, Sussex. 



9. Eugeniacrinus quinquedactylus, Schl. ; Oxfordian, Wurtemberg. 

 10. Bourgueticrinus ellipticus, Mill. ; Chalk, Kent. 



Protaster (fig. 7, 6), and Lepidaster (fig. 7, 5), are Silurian star- 

 fishes, presenting many anomalies, and scarcely referable to 

 any existing families. The living starfish (Ophiocoma) which 

 is most like Protaster, has been dredged up alive from a 



