The Marine Fauna of the Mergui Archipelago. 161 



Localities. — St. XXX., Fly Island, Observation Island, and south-west of 

 Domel Island, 8 to 15 fathoms, rock and sand, diver and small dredge (two 

 examples). St. XXXII, South-west of Domel Island, 26 to 29 fathoms, sand 

 and mud, large dredge (nine examples). St. XXXIII., Christmas Island 

 Group, 8 to 23 fathoms, rock and sand and mud, diver and dredge (two 

 examples). 



The species was not found either by the " Investigator " or by the 

 " Siboga " expeditions, and it has not hitherto been recorded from the Mergui 

 Archipelago. It has, however, been taken from the Maldive and Laccadive 

 Archipelagoes, and it is known to have a wide geographical distribution, for 

 examples have been also taken from the Bed Sea, Zanzibar, Mozambique, 

 Port Natal, Samoa and the Fiji Islands. 



(6) Ophiomastix venosa Peters, 1852. 



There are in the collection two examples of this species from one station. 



There is no mistaking this splendid example of the Ophiuroidea, for the 

 skin-covered disc with its few stout blunt spines and its peculiar markings, 

 and the very large club-shaped upper arm-spines (generally every fourth 

 one is clubbed), are very distinctive. While Lyman (1882) says that there 

 are "usually one, rarely two tentacle- scales " (p. 175), both my examples 

 have two tentacle-scales for nearly two-thirds the length of the arm, and 

 thereafter towards the arm tip only a single scale. 



Locality. — St. XXXII., South-west of Domel Island, 26 to 29 fathoms, 

 sand and mud, large dredge (two examples). 



The species is well known as an inhabitant of the western parts of 

 the Indian Ocean, having been taken from Mozambique and from Zanzibar, 

 and also from the Maldive and Laccadive Archipelagoes, where Bell (1903) 

 found it "common in the Maldives." But as it was not found either by 

 the "Investigator" (1898), or by the "Siboga" (1905), and it has not 

 hitherto been recorded farther east than the Maldives, its appearance in 

 the Mergui Archipelago adds considerably to its range of geographical 

 distribution. 



(7) Ophiothrix foveolata Marktanner-Turneretscher. 



The species is represented by two examples from different stations. 

 Each has a disc-diameter of 5 '5 mm. and an arm-length of about 27 mm. 



It is some satisfaction to find that 0. picteti Loriol, is now regarded as 

 synonymous with Brock's 0. foveolata, and that Koehler, after an examination 

 of the original example of 0. foveolata, is satisfied that his new species 

 0. insidiosa (1898) is not sufficiently distinct to justify its retention. Of 



