86 MR. A. W. WATERS ON 
Sow., from the same locality are undistinguishable from the shape 
of the colony ; ard when dealing with the earlier descriptions, 
where the form of growth was considered the most important 
character, it is impossible to judge which species is referred to. 
Tt is also said to occur encrusting shells and stones. 
There are 16 tentacles. There are small oral glands which 
seem to be attached to the sheath. The contents of the pore- 
tubes at a slight distance from the external surface of the zocecium 
are large elongate cells, with a central nucleus, but near the 
surface the cells are smaller. 
A figure of the operculum (fig. 25) and mandible (fig. 24) of 
Escharoides rosacea, Busk, from Loch Tyne is given for com- 
parison. The operculum of rosacea has a thin muscular ridge at 
each side and the lower edge of the operculum is nearly straight. 
The mandible is semicircular, and has a small median lucida and 
a thinner part at each side, both opercula and mandible being of 
the Porella type. The mandible in rosacea is however lateral 
instead of being median. 
I have referred at some length under Cribrilina punctata, Hass. 
(p. 62), to the three species of common Arctic Bryozva said to 
have been found in the Antarctic by Hooker, in the ‘ Erebus’ 
and ‘Terror,’ and have suggested the probability of an error in 
labellmg having occurred. 
The mandibles of the ‘Erebus’ and ‘Terror’ specimen are 
characteristic of L. Sarsi, and fall within the range of the Arctic 
specimens examined. 
Loc. Spitzbergen, 20-60 fath.; Greenland; Finland (Sm.) ; 
Kara Sea, 49-65 fath. (Levinsen); Jan Mayen, 160-180 metres 
(encrusting, no avicularia) ; Franklin Pierce Bay, Smith’s Sound, 
18 fath. (Busk); Gulf of St. Lawrence (Hincks); Northumber- 
land Island (Hennig); off Franz-Josef Land, lat. 79° 55’ N., 
long. 51° 0’ E. (Ridley). According to Hooker and Busk, lat. 
74° 0'S., long. 172° 0’ E., 330 fath. 
Jackson-Harmsworth Exp.: off glacier between Cape Flora 
and Cape Gertrude, about 30 fath. ; off Cape Mary Harmsworth, 
53-93 fath. 
45. Porina THBULOSA, Norman. 
Lepralia tubulosa, Norman, Rep. Brit. Assoc. 1868, p. 308. 
Anarthropora monodon, forma minuscula, Smitt, “ Krit. Fort.” 1867, 
pp. 7 & 65, pl. xxiv. figs. 20 & 22. 
J*or other synonyms see Miss Jelly’s Catalogue. 
The suboral pore enters the peristome above the operculum. 
