PLATE IX. 



Aspidodiadema antillarum A. Ac. 



Fig. 1. Specimen with spines, test 11 mm. in diameter, seen in profile. 



Fig. _. Same with the spines cut off, seen facing an ambulacra! area, showing the sheathed pedicellarite. 



Fig. 3. Portion of test of a specimen 11 mm. in diameter, seen from the actinal side ; denuded. 



Fig. 4. Portion of test of same as Fig. 3, seen from the abactinal pole ; denuded. 



Fig. 5. Actinostome, with termination of the adjoining ambulacral areas, showing the suckers, the gills, 



and the large buccal tentacles of Fig. 2. 

 Fig. 6. Portion of denuded test of specimen 11 mm. in diameter, seen facing one of the ambulacral 



areas. 

 Fig. 7. The same as Fig. 6, seen facing one of the interambulacral areas. 

 Fig. 8. Denuded test of specimen 9 mm. in diameter, seen from the actinal side. 

 l). Genital ring of same, somewhat more magnified. 

 LO. One of the sheathed ambulacral pedicellaria?, greatly magnified. 

 Fig 11. Long temmed, long-headed trifid flexible pedicellaria, placed above ambitus. 

 Fig. !_. Magnified view of a piece of the basal part of a primary radiole. 

 Fig. 13. Large hyaline, globular, short-stemmed ambulacral sphxridia, found near the abactinal system ; 



lified. 

 Fig. 14. Smaller, long-stemmed actinal ambulacra] sphseridia ; magnified. 

 Fig. 15. Young aheathed pedicellaria. 



Fig. 16. Small, short-headed, short-stemmed trifid ambulacral pedicellaria. 

 Fig. 17. Actinostome of young Aspidodiadema measuring 5 mm. in diameter. 

 Fig. 18. Genital ring and anal system of same specimen : neither the ocular nor the genital pores are as 



yet formed in this specimen. 

 Fig. 19. Young Aspidodiadema li mm. in diameter, seen from the actinal side : the primary spines are 



cut off. 

 i 10. The same as l'ig. 19, seen from the abactinal pole, showing the anal proboscis. 

 I I Genital ring of small Aspidodiadema 3.5 mm. in diameter: the genital pores are already 



ned. 



