16 
THE VOYAGE OE H.M.S. CHALLENGER. 
maimer. Anterior . surface obscurely fibro-reticulate, sparsely furnished with subtubular 
pores. Zooecia on the front of the branches, immersed or very slightly prominent, those 
of the outer sides of the branches tubular, slightly expanded towards the orifice, which is 
more or less elliptical, with an entire border often much produced on one side ; dorsal 
surface finely sulcate with minute pores in the sulci. Ooecia dorsal, subglobular or 
gibbous, the surface reticulate or coarsely punctured, Aperture tubular, lateral (from 
which a very slender rib stretches across to the opposite side, Hincks). Diameter of 
branches 0'5 to 0‘6 mm., and of orifice about O’l mm. 
Habitat.- — Station 320, lat. 37° 17' S., long. 53° 52' W., 600 fathoms, green sand. 
[Arctic Seas, Loven ; coasts of Scandinavia, Pantoppidan, Sars, Macandrew ; Shetland, 
Barlee ; Hebrides, Norman ; Nova Zembla ; Greenland, Liitken ; St. Georges Banks, Smitt 
and Harger.] 
§§ b. Ooecia anterior, either wholly or in part ; dorsal surface granular or 
finely striate. 
(3) Hornera violacea, Sars. 
Hornera violacea (, forma violacea), Smitt, loc. cit., p. 404, Tab. vi. fig. 6-9 ; Sars, Geol. og 
zool. Jagtt. Reise TroncLhj., 1862, Nyt Mag. Nat.-Vid., vol. xii. p. 282; Busk, Brit. Mus. 
Cat., pt. iii. p. 18, pi. xviii. figs. 1-4; Norman, Shetl. Dredg., Rep. Brit. Assoc., 1867, 
p. 310 ; Hincks, Brit. Mar. Polyz., i, p. 469, pi. lxvii. figs. 6-8, pi. lxii. figs. 2, 3, 
Pustulopora orcadensis, Bk,, Quart. Journ. Micr. Sci., 1860, vol. viii. p. 214, pi. xxxix. 
figs. 1, 2. 
Character.— Zoarium more or less of a violet colour, branched, straggling ; branches 
short, truncate, irregularly dichotomous. Zooecia very irregularly disposed, sometimes 
crowded into small fasciculi, usually elongated ; surface punctate (not reticulate) ; dorsal 
surface granular, or very finely striated with minute pores, often a rib-like elevation 
down the centre of the branch. Ooecia elongated, situated in the axils of the branches, 
usually more towards the dorsal aspect ; surface smooth, finely punctate, with a thin 
median costa; orifice bilabiate near the top. Diameter of branches 0'4 to 0’7 mm., and 
of orifice O’ 12 mm. 
Habitat. — Station 151, off Heard Island, 75 fathoms, volcanic mud. 
[Arctic and Northern Seas, generally distributed ; Shetland.] 
§ fi. fenestrata (subgenus Retiliornera). — Branches sub-parallel, connected by 
transverse tubules, so as to form an expanded frond with quadrangular 
fenestrse. 
Retiliornera (pars), Kirch enpauer, Cat. iv. of the Museum Godeffroy, 1869 ; Busk, Brit. Mus. 
Cat., pt. iii. p. 19. 
