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species, on Retepora and Canda respectively ; Stat. 310 [ji Metres), one species, on Retepora\ 

 and Stat. 321 (82 Metres), one species, on Schizoporella. 



It is thus clear that the Entoprocta and Ctenostomata of the Malay Region, as in other 

 parts of the world, are in the main shallow water forms. Of the former group, with the exception 

 of two abyssal species of Loxosoma (469, 275 Metres) and of others from 73 to 113 Metres, 

 whose distribution may be considered to be affected by that of their "host"', Barenlsia seems to 

 descend to a slightly greater depth than the Loxosomatidae. 



The distribution of Entoprocta and Ctenostomata in the Archipelago, as revealed by 

 these records, is curiously unequal. Thus from the whole series of Stations (93 — 109) from the 

 Sulu Sea, the only member of either group was Amathia convoluta (? sp.), from Stat. 99 (16— 

 23 Metres), although this particular Station was rich in Polyzoa generally, and was, moreover, 

 well within the limits of depth at which the two groups were found to flourish in other regions. 



Ctenostomata were obtained principally in two well marked groups of Stations : 

 (I) off the N. W. extremity of New Guinea, including the region from the Aru Islands to the 

 S. coast of Ceram, and the S. point of Halmaheira (Djilolo); (II) off the chain of Islands 

 stretching from Java to Flores, in the Straits of Makassar and on the other coasts of Celebes, 

 and just extending to the Sulu Sea. Only one Station (133, Talaut Is) at which Ctenostomes 

 were found falls outside these limits. The map published by Prof. Max Weber in his preliminary 

 account v ) of the Expedition shows that the two principal areas correspond with two relatively 

 shallow water plateaux separated by deep water. One of these extends from the N. coast of 

 Australia to New Guinea, and the other from Borneo through Java and other Islands to Flores, 

 and, in other directions, to Celebes and the Sulu Sea. It is noteworthy that the coast of Timor, 

 which is separated from Flores by deep water, has yielded no Ctenostomes, though Elzerina 

 blainvillii was recorded by Lamocroux from Timor. 



The individual Stations from which Ctenostomes were obtained in greatest abundance 

 were: — from area (I), Stat. 164, W. of the N. end of Xew Guinea (9 species) and Stat. 273, 

 Aru Is (6 species): — and from area (II), Stat. 50, W. end of Flores (5 species); Stat. 64, 

 Tanah Djampeah, X. of Flores (4 species); and Stat. 71, Makassar (6 species). The depth of 

 none of these dredgings exceeded 40 Metres. At all these Stations a considerable number of 

 other Polyzoa were obtained, Stat. 164 being specially rich in these animals. It has been pointed 

 out by Prof. Weber 2 ) that Stations 164 and 273 were characterised by the richness of their 

 fauna in general. 



A careful tabulation of the occurrences of the individual species has failed to reveal 

 anything that could be held to justify the division of the entire area covered by the 'Siboga' 

 dredgings into sub-regions. Omitting the two species [Alcyonidium polyoum and Elzerina 

 blainvillii) which were obtained from Torres Straits, outside the 'Siboga' area, 18 species of 

 Ctenostomata are described in the present Report. Of these, 14 occur in the first of the large 

 areas indicated above, and 13 in the other area. The two species found in the rather isolated 



1) Weber, M.. 1900, u Die Niederlünd. 'Siboga' Exped.". Petermann's Geogr. Mitth.. Heft VIII. p. 3 (sep.). 



2) Weber, M.. 1902, Monogr. I, "Introd. et Descr. de 1'Expéd., pp. 72, 124 — 126. 



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