5 R. granifera. 



6 R. gyrinus. 



7 R. margaritula. 



8 R. spinosa. 



9 R. subgranosa. 

 10 R. tuberculata. 



Lamarck. 



Deshayes. 



Deshayes. 

 Lamai'ck. 



Beck. 

 Broderip. 



11 R, tuberosissima. Reeve. 



b Madras Coast.* 



a Philippines. 



b Madras Coast.* 



c Port Blair, An- 

 daman s. 



Mediterranean and 

 Eastern Seas. 



Indian Seas. 



a Ceylon.* 



b Madras Coast.* 



Bay of Manilla. 



a Malacca. 



b Vizagapatam.* 



c Port Blair, An- 

 damans. 



Philippine Islands. 



Dr. Waiter?, 



