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The preceding list gives a complete statement of all the specimens of Entoprocta and 

 Ctenostomata which I have found among the 'Siboga' dredgings. It may be remarked, in the 

 first place, that the conditions which are favourable for the occurrence of either of these groups 

 appear to be favourable for that of the other; — since Entoprocta and Ctenostomata were 

 found in company in a considerable number (17) of the Stations. Only 42 of the Stations have 

 yielded both groups or one of them, out of a total of about 135 Stations at which Polyzoa were 

 obtained. Entoprocta are represented at 30 Stations, and Ctenostomata at 29 Stations. 



So far as the Loxosomatidae are concerned, the distribution is no doubt affected by that 

 of the animal on which they are found. Loxosoma cocciforme was discovered in the material 

 from Stat. 156, at a depth of 469 Metres. I believe this to be the greatest depth from which 

 any species of this genus has been obtained; but it seems natural to suppose that this exceptional 

 depth depends largely on the fact that Siphonicytara, the Cheilostome Polyzoon on which the 

 Loxosoma was found, is in some way adapted for an abyssal existence. Loxosoma sluiteri, on 

 Phascolion, was obtained from Stat. 105, 275 Metres. With these exceptions, only one of the 

 above Stations exceeds 100 Metres; namely Stat. 166 (118 Metres), at which a single Ctenostome, 

 Buskia setigera, was found. Nolella papuensis and two species of Loxosomatidae occurred at 

 Stat. 204 (75- — 94 Metres); while Valkeria atlantica is recorded from Stat. 117 (80 Metres) and, 

 in company with two Entoprocta, from Stat. 318 (88 Metres). All the rest of the Ctenostomata 

 were found at depths of less than 60 Metres, and most of them in still shallower water. 



The majority of the Entoprocta similarly come from dejiths of less than 60 Metres. 

 Those from greater depths, in addition to the records indicated in the preceding paragraph, 

 are: - ■ Stations 319, 320 (82 Metres), two species of Barentsia-, Stat. 318 (88 Metres) one 

 Barentsia, and one Loxosoma on a Cheilostome (Couesc/iarellina). The remaining records 

 exceeding 60 Metres consist entirely of species of Loxosoma growing on Cheilostomes, and are 

 as follows: Stat. 116 (72 Metres), one species, on Retepora; Stat. 305 (113 Metres), two 



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