PLATE III. 



Photographs of Casts showing Oral Surface. 



Fig. Page. 



1. Caradacaster caractaci, Gregoiy sp. — Ordovician (Caradocian) ; Marsh- 



brook, Church Stretton, Shropshire, x 2, Museum of Practical 

 Geology, London, no. 4/30. 82. 



2. Coccaster bulbiferus, n. sp. — Upper Silurian (Lower Ludlow) ; Leint- 



wardine, Herefordshire, x 4. Ludlow Museum. 76. 



3. Belaster ordovicm, n. sp. — Upper Ordovician (Ashgillian) ; Thraive 



Glen, Ayrshire, x 4. Mrs. Gray's Collection, no. D. 44 c. 73. 



4. Ditto (?). — Upper Ordovician (Lower Bala) ; near Bala Lake, "Wales. 



X 3^. T. Ruddy Collection, British Museum (Nat. Hist.), no. 



E. 13532. 74. 



5. Mesopalgeaster compUcatus, n. sp. — Upper Ordovician (Ashgillian); 



Thraive Glen, Ayrshire, x 4. Mrs. Gray's Collection, no D. 74 c. 88. 



6. Glrvanaster sciilptus, n. sp. — Ibid, x 4|. Mrs. Gray's Collection, 



no. D. 169. 71. 



7. Garactacaster caractaci, Gregory sp. (?) — Upper Ordovician (Lower 



Bala) ; near Bala Lake, "Wales, x 7. T. Ruddy Collection, British 

 Museum (Nat. Hist.), no. E. 13531. 83. 



8. Mesopalssaster jprimus, n. sp. — Upper Ordovician (Ashgillian) ; Thraive 



Glen, Ayrshire, x 4. Mrs. Gray's Collection, no. D. 70 c. 86. 



