ANTAEUTIO BENTHOS
46
composition of the fauna is as follows (number of species in parenthesis) :
Pachyclavularia (2), Caligorgia (3), Primnoella (6), Lycurus (2),
Thouarella (5), Ceratoisis (l), Primnoisis (6), Mopsea (2), Echinisis ( l ) ,
Callozostron ( l ) , Ascolepsis (2) and Leptogorgia (1) (Molander, 1929 ;
Thomson and Rennet, 1931).
The difficult genus of pennatularians, Umbellula, has recently been
revised by Broch (1959). Species of Urnbellula occur in the ocean basins
of the world. Apart from a single record of U . durissima K6Mcker
from 3 185 m in the Antarctic, Broch believed that the sole Antarctic
species is U . lindahli Kallicker. This latter form known from the Atlantic,
Indian and Pacific Oceans in depths from 310 to 5 300 m, has been
recorded from Antarctic waters in depths from 77 to 3 560 m. It is
almost certainly circum-Antarctic in distribution. Pasternak (1 962)
basing his conclusions largely on the material collected by the Soviet
Antarctic expeditions disagreed with Broch’s conclusions, and demonstrated that Umbellula magniJEora can be satisfactorily separated from
U. lindahli. Both species are widely distributed in other areas as is a
third species recorded from the Antarctic by Pasternak, Umbellula
thomsoni .
The only other known pennatularim seems to be Kophobelemnon
paucifirum described by Molander from off the Antarctic Peninsula.
6. Hydroidea
Naumov and Stepaniants (1962) have given a short general account
of the Antarctic hydroid fauna and its affinities as an introduction to
the systematic study of the material collected by Soviet Antarctic
Expeditions. This is in fact one of the few general accounts of the
Antarctic members of the group although systematic accounts have been
contributed by Browne (1902), Hartlaub (1904), Jaderholm (1904, 1905,
1926), Billard (1906, 1914), Hickson and Gravely (1907), Ritchie (1907,
1909, 1913), Vanhoffen (1911), Totton (1930), Briggs (1939), Broch
(1948), Manton (1940) and Naumov and Stepaniants (1958, 1962).
The last named authors (1962) estimate that about 178 species of Thecaphora have been recorded from Antarctic waters, although critical work
may reduce this number. Although a large number of species have
been recorded, hydroids do not make up a great quantity of bottom
material.
There are a high percentage of endemic forms, the genera Abietinella,
Billardia, Oswaldella and Stegella being confined to the Antarctic and
Subantarctic zones. Naumov and Stepaniants (1962) cannot make a
clear distinction between the hydroid fauna of the Subantarctic and the
46
composition of the fauna is as follows (number of species in parenthesis) :
Pachyclavularia (2), Caligorgia (3), Primnoella (6), Lycurus (2),
Thouarella (5), Ceratoisis (l), Primnoisis (6), Mopsea (2), Echinisis ( l ) ,
Callozostron ( l ) , Ascolepsis (2) and Leptogorgia (1) (Molander, 1929 ;
Thomson and Rennet, 1931).
The difficult genus of pennatularians, Umbellula, has recently been
revised by Broch (1959). Species of Urnbellula occur in the ocean basins
of the world. Apart from a single record of U . durissima K6Mcker
from 3 185 m in the Antarctic, Broch believed that the sole Antarctic
species is U . lindahli Kallicker. This latter form known from the Atlantic,
Indian and Pacific Oceans in depths from 310 to 5 300 m, has been
recorded from Antarctic waters in depths from 77 to 3 560 m. It is
almost certainly circum-Antarctic in distribution. Pasternak (1 962)
basing his conclusions largely on the material collected by the Soviet
Antarctic expeditions disagreed with Broch’s conclusions, and demonstrated that Umbellula magniJEora can be satisfactorily separated from
U. lindahli. Both species are widely distributed in other areas as is a
third species recorded from the Antarctic by Pasternak, Umbellula
thomsoni .
The only other known pennatularim seems to be Kophobelemnon
paucifirum described by Molander from off the Antarctic Peninsula.
6. Hydroidea
Naumov and Stepaniants (1962) have given a short general account
of the Antarctic hydroid fauna and its affinities as an introduction to
the systematic study of the material collected by Soviet Antarctic
Expeditions. This is in fact one of the few general accounts of the
Antarctic members of the group although systematic accounts have been
contributed by Browne (1902), Hartlaub (1904), Jaderholm (1904, 1905,
1926), Billard (1906, 1914), Hickson and Gravely (1907), Ritchie (1907,
1909, 1913), Vanhoffen (1911), Totton (1930), Briggs (1939), Broch
(1948), Manton (1940) and Naumov and Stepaniants (1958, 1962).
The last named authors (1962) estimate that about 178 species of Thecaphora have been recorded from Antarctic waters, although critical work
may reduce this number. Although a large number of species have
been recorded, hydroids do not make up a great quantity of bottom
material.
There are a high percentage of endemic forms, the genera Abietinella,
Billardia, Oswaldella and Stegella being confined to the Antarctic and
Subantarctic zones. Naumov and Stepaniants (1962) cannot make a
clear distinction between the hydroid fauna of the Subantarctic and the