PLATE XXV. 



PltOTOOIDARIS ACUAKIA, ii. sp. (Page 203.) 

 Fig. 



1. Mould of a portion of a crushed test, showing numerous interambulacral plates 



and spines, X 2. 1 a. Portion of the same, showing a tubercle and parts 

 of two spines, X 25. 1 b. Portion of the same, showing several plates 

 and large and small spines, X 5. East of Barnstaple. Museum of Prac- 

 tical Geology. 



2. Another specimen, probably belonging to the same test, showing remains of 



the lantern-apparatus, nat. size. 2 a. Portion of one of the bones of the 

 lantern, X 10. East of Barnstaple. Museum of Practical Geology. 



Lepidesthes ? devonicans, Whidbome. (Page 200.) 



3 a. Wax cast of some interambulacral plates from the test figured on PI. XXIV, 

 showing their shape and ornamentation, X 5. 3 b. Wax cast of some 

 ambulacral plates, X 5. 3 c. Portion of an interambulacral plate, showing 

 a tubercle, X 25. 3 d. Portion of a spine, X 25. 3 e. Another spine, 

 X 10. 3/. An ambulacral plate, showing its thickness, X 10. Pilton 

 Beds, North Devon. Museum of Practical Geology. 



