[. 295 ] 



XV. On new Forms of Actiniaria dredged m the Beep Sea ; with a Description of 

 certain Pelagic Surface-swimming Species. By H. N. Moseley, M.A., F.R.S., 

 Fellow of Exeter College, Oxford, late Naturalist on board H.M.S. ' Challenger.' 

 {Communicated by Dr. J. Mtjrie, F.L.S.) 



(Plate XLV.) 



Bead February loth, 1877. 



JL HE deep-sea Actiniaria herewith to be described were obtained on various occa- 

 sions by the dredge or trawl during the voyage of H.M.S. ' Challenger.' Actiniaria of a 

 variety of forms were obtained in deep water frequently during the Expedition and in 

 very various localities, and only a small part of these are accounted for in the present 

 paper. Several circumstances, such as rough weather, and the fact that, as frequently 

 was the case, the dredge or trawl was only got up to the surface at nightfall, combined 

 to prevent all the Actiniaria obtained being worked at in the fresh condition, and very 

 often, when other circumstances were favourable, some more important subject called 

 for immediate attention. A few of what appeared to be the most interesting forms were, 

 however, sketched and partly worked out whilst the animals were fresh, and the 

 results are here given. The pelagic Actinias (Minyadina?) were obtained either with 

 the surface-net or in the trawl. 



Eamily ACTINIAE^]. 



Subfamily Minyadin^:. 



Nautactis ptjrpuketjs, n. sp. (Plate XLV. figs. 1 & 2.) 



A small floating Actinia was found amongst the contents of the towing-net on 

 August 26th, 1874 lat. 13° 39' S., long. 150° 53' E., between the New Hebrides and the 

 north-east coast of Australia. The animal was very small, not more then 7 millhns. in 

 height, when measured with the parts about the mouth protruded. The body is cylin- 

 drical, with the aboral surface much flattened. The costse are slightly elevated rounded 

 ridges, 24 in number, nearly equal in size, and without tubercles. The tentacles are 12 in 

 number, disposed in two series, 6 primary larger ones lying nearer the mouth than the 

 6 somewhat smaller secondary ones ; they are simple, very short indeed, reduced 

 in fact to rounded conical tubercles. Between the tentacles at the margin of the disk 

 are a series of small tubercles of triangular outline. The mouth is linear. The costal 

 and aboral surfaces of the animal are of a chocolate colour with a tinge of lilac.- Near 

 the margin of the disk is an irregular line of bright orange-yellow. The margin of the 

 mouth is of a dark burnt-sienna colour. Erom it radiate out streaks of chocolate 

 colouring, which fork to embrace the bases of the transparent white tentacles and the 

 intertentacular tubercles. These tubercles are of a glistening but opaque white, with 

 bright orange colouring on their lateral borders, and a dark spot in their centre. 



SECOND SERIES. — ZOOLOGY, VOL. I. 2 K 



