1026 DR. G. HKliJ5ERT i'OWLEll OX THE [DeC. 13, 



by numerous observations at all depths on successive days in a small 

 area, and even these cannot he safely applied to a species unless 

 it occurs constantly and in fair number in a large percentage of the 

 hauls. The table of Phieodarian captures given on pp. 1022-3 

 would seem at first sight to point to about 100 fathoms as the 

 upper limit of all the species except Cceloplegma murrayanum ; but 

 the weakness of such an inference would lie in the fact that none 

 of them were captured with anything like regularity in the Meso- 

 j)lanktou. That the argument would be false is shown by the 

 fact that two of them were taken by Sir John Murray at the 

 surface from H.M.JS. ' Triton ' in the same waters. 



All the conclusions that can be drawn for the Faeroe Channel, 

 from so few observations as those in the table, are : — 



(1) That Cceloplegma murrayanum is both epiplanktonic and 

 mesoplanktonic, extending to at least 350 fathoms (19 a) and 

 a temperature of 33° Fahr. (13 _r/). The large number of specimens 

 taken at 13^ and 19 «, and the small number taken at or near the 

 surface, showed that the deep specimens were not merely dead 

 and sinking to the bottom. 



(2) That Aulacantha Icevissima and Aulosphcera Jle.vuosa may 

 occur at considerable depths in the Mesoplankton ; since the 

 ' Triton ' results showed them to exist at the surface also, they 

 are, like Cceloplegma murrayanum, to be regarded as epiplanktonic 

 and mesoplanktonic. Though not present in such numbers as the 

 first species, they were plentiful enough to make it extremely 

 improbable that the specimens were dead and sinking. 



(3) That A'uloyraphis moorensis and Auloceros trigeminus, var., 

 occur in the Mesoplankton, but it does not appear whether they 

 are confined to it or not. 



Attlacantha l^vissima Haeckel. (Plate LXVI. fig. 3.) 



The youngest specimens referable to this genus in the ' Research ' 

 collections agreed entirely with Haeckel's description of A. la'vis- 

 sima, except for the presence of a few extremely minute teeth on 

 the larger spines. Larger specimens, ho«'ever, with a central 

 capsule about "4 mm. in diameter, and spines at least -9 mm. in 

 length and calymma about 2 mm. in total diameter, exhibited a 

 distinct denticulation (Plate LXVI. fig. 3). As A. Utvissima has 

 been described only from the Faeroe Channel, it is probable that 

 my specimens belong to the same species as those of Haeckel. I 

 have therefore retained the name for " the smoothest " species 

 described up to the present. 



For the horizons of capture, see the table on p. 1022. 



AuLoaRAPHis (Aulographonium) moorensis *, sp. n. (Plate 

 LXVI. figs. 2, 4.) 



Definition of the Species. — Eadial tubes rounded proximately, 



' With this new species 1 am glad to associate the name of Captain W. 

 Usborne Moore, E.N., ol' H.M.S. ' Research,' to whose help I owe no small part 

 of such success as my midwater experiments attained. 



