28 
Proceedings of the Royal Society of Edinburgh. [Sess. 
0-46-0'80 mm. 
0T8-0-30 mm. 
0-30-0-32 mm. 
0-24-0-29 (0-45) f mm. 
0-16-0‘18 mm. 
19 -2 - 2 mm. 
0 - 8 -0’9 mm. 
unites it to the stem, and it stands upright at right angles to the plane in 
which the normal hydrothecse lie, thus resembling the hydrotheca of some 
epizoic species of Thyroscyjphus. The resemblance to Thyroscy'phus is still 
more pronounced where, as in one case from Cape Royds, a stolon-like 
fascicle-tube gives rise to these free hydrothecm ; but the real condition is 
betrayed by the presence of a normal Sertularella cumberlandica branch 
which springs from the same tube. 
The branches of the colony from the Bay are laden with elegant 
gonangia. 
Dimensions . — 
Internode, length * . 
diameter . 
Hydrotheca, portion adnate 
„ free . 
diameter at mouth 
Gonangium, length j 
greatest diameter 
Localities. — Bay (east of Cape Royds), 10-20 fathoms, May 1908, single 
fine colony with many gonangia; 7-20 fathoms, June 1908, fragments. 
M £ Murdo Sound, 25-50 fathoms, 6th July 1908 ; not common. 
Off Cape Royds (south) 20-50 fathoms, July 1908, not common; 30-60 
fathoms, 15th August 1908 ; 30-80 fathoms, August 1908, with gonangia. 
Distribution. — Sertularella cumberlandica has been regarded only as a 
sub-antarctic species ; the above records add it to the Antarctic fauna, but 
on the opposite side of the Antarctic Continent. The only previous records 
are those of Jaderholm, who describes it as occurring at various stations in 
Cumberland Bay, South Georgia. 
Remarks. — Vanhoffen (1909, p. 327) identifies Jaderholm ’s Sertularella 
cumberlandica with Sertularella subdichotoma, Kirchenpauer. In so doing, 
however, he has failed to take account of the great difference in habit which 
characterises colonies of the two species. Kirchenpauer describes the type 
specimens of S. subdichotoma as being “ sehr feine, schwach verastelte 
Stammchen, etwa 3 cm. lang, Stamm, Aste und Zweige alle von gleicher 
Dicke ” (Kirchenpauer, 1884, p. 46). Hartlaub writes of the same species : 
“ meistens vielfach mit einander durchklammerende verbundene, mono- 
* From any point on an internode to the corresponding point in its predecessor or 
successor. 
t The figures given are those of primary hydrothecse ; those within the parentheses 
show to what length reduplication of the margin may prolong the free portion. 
I Excluding terminal tube, which measures 0‘02 mm. long by 0‘015 mm. diameter at 
the mouth. 
