22 Proceedings of the Royal Physical Society. 



The fifteen Echinoids in the present collection are as follows: — 



1. Phyllacanthus bacxdosus (Lam.), A. Ag. 



2. Diadema saxatile, Linn. 



3. Echinothrix turcarum, Ret. 



4. Astropyga radiata, Gray. 



5. Asthenosoma Grubei, A. Ag. 



6. Echinometra lucunter, de Blainv. 



7. Salmacis bicolor, Agass. 



8. Salmacis Dussumieri, Agass. 



9. Salmacis sulcata, Agass. 



10. Salmacis globator (Bell). 



11. Mespilia globulus, Agass. 



12. Laganum dcpressum, Less. 



13. Laganum decagonale, de Blainv. 



14. Laganum sp. 



15. Lovenia subcarinata, Gray. 



The most noteworthy species in this collection are Asthenosoma Grubei 

 and Salmacis globator. 



A. Grubei, of interest in itself as a specimen of a little known species, has 

 an additional claim to notice since its occurrence in the Mergui Archipelago 

 extends to the Indian Ocean the range of a species that was previously 

 known only from the Philippines and Dutch East Indies. 



Salmacis globator has been recorded previously from Singapore and the 

 Pacific, but never from the Indian Ocean. 



1. Phyllacanthus baculosus (Lam.), A. Ag. 

 A. Ag., Rev. Ech., p. 388. 1 

 Locality. — XXIX., 2 High Peaked Island, coral reef. 



A large specimen, 60 mm. in height and 75 mm. in diameter. Most of 

 the spines are of a very light-green colour banded with faint purple. 



Distributed from the Ked Sea, Zanzibar, Mozambique, and Mauritius, 

 to Timor and the Philippines. 



2. Diadema saxatile, Linn. 

 A. Ag., Rev. Ech., p. 27 J. 

 Localities. — III., Iron Island, shore pools; XIV. and XXIX., Bushby Island 

 and High Peaked Island, coral reefs. 



1 References are given only to Agassiz's Revision, except in the case of species described 

 since the date of that work. 



'-' These numbers refer to the Stations. 



