HOLOTHUEIOIDEA. 1'J'J 



Family : ASPIUUCHIKUT.K. 

 Actinopyga mauritiana (Quoy and Gaimard). 



Holothuria mauritiana, Q. & Gr., 1833. Miilleria varians, Selenka, 1S67. Miilleria 

 mauritiana. Semper, 1868. See also Theel (7). 



One specimen from the lagoon inside the Reef, Galle. Length, 140 millims. 



The specimen possesses most of the characters of the species. There are, however, 

 no white rings around the dorsal papillae. 



On the ventral surface there is a well-marked white symmetrical patch which is 

 quite distinct from the brown dorsal surface. 



In Theel's description this marked difference in colouring is not emphasised, and 

 he leads one to believe that the brown on the dorsal surface is gradually changed for 

 the lighter colour of the ventral surface. It is interesting to note that the specimens 

 of this species, which Professor Herdman kindly examined for me, with Professor 

 Jeffrey Bell, in the British Museum, showed transitions between those described 

 by Theel and the striking condition seen in the Ceylon specimen. So that it is 

 evident that the nature of the colouring of the ventral surface, with relation to its 

 distinctness from that of the dorsal surface, is susceptible of considerable variation in 

 the species. 



The pedicels of the ventral surface are capable of great extension, and have white 

 sucking discs. The white integument of the ventral surface is closely covered with 

 small but conspicuous pores, suggesting the singular appearance of a white colony oi 

 the Compound Ascidian Leptoclinum. 



Distribution : Indian Ocean from E. Africa to East Indies ; Funafuti, in the 

 central Pacific. 



Actinopyga serratidens, n. sp. Plate III., figs. oG-41. 



One specimen from the lagoon inside the Reef, Galle. Length, 180 millims. 



Colour of spirit specimen is brownish -black. 



The tentacles are partly retracted, so that it is difficult to ascertain their exact 

 number. There are, however, 20 tentacular ampullae, so that there will also be 

 20 tentacles. The colour of the tentacles is dark brown. 



The mouth is ventral, and is surrounded by a distinct brim formed by a folding of 

 the integument. The anus is surrounded by live distinctly serrated teeth, each tooth 

 being 3 millims. in length. 



The pedicels are irregularly scattered over the ventral surface, showing no 

 arrangement in rows. They are distinctly cylindrical with well-developed sucking 

 discs. The dorsal surface is covered with papillae, which are more slender than the 



