1912-13.] Hydroids of British Antarctic Expedition, 1908. 19 
to that of Ophiodes arboreum, but without nematophores, and of less 
robust growth. With Halecium macrocephalum also I reckon Jaderholm’s 
Halecium arboreum from the Falkland Islands and their neighbourhood, 
and from South Georgia (Jaderholm, 1905); but Vanhoffen’s Halecium 
robustum from the Antarctic Gauss Station (Vanhoffen, 1910) bears more 
resemblance to the finer Halecium sessile , Norman. 
Family Campanularim:. 
Campanularia Icevis, Hartlaub. 
Campanularia Ixvis, Hartlaub, 1905, p. 565, fig. A- 
Idem , Hickson and Gravely, 1907, p. 25, pi. iv. fig. 26. 
Idem , Vanhoffen, 1909, p. 298, fig. 18. 
The material of this species, although it has been obtained from two 
localities, is scanty, and the trophosomes are in poor condition, the majority 
of the hydrothecse being detached from their stems. The trophosomes, 
however, agree with the figures of Hartlaub and of Vanhoffen, less well 
with that of Hickson and Gravely. There are differences in size to be 
noted, for while our specimens are rather larger than those originally 
described by Hartlaub (judging from his magnified figure), and agree 
fairly closely with the measurements given by Hickson and Gravely, yet 
they correspond only to the minimum given by Vanhoffen. Both Hartlaub 
and Vanhoffen emphasise the absence of annulations at the base of the 
pedicel, but, although some of our specimens are smooth, a few bear very 
faintly marked corrugations. 
Gonosome . — Hickson and Gravely have already drawn attention to the 
dissimilarity which exists between the gonangia described and figured by 
Hartlaub and those found by themselves. It is extraordinary that our 
examples are different from either. They are twice as tall, and are set on 
moderately long stalks ornamented with about six to eight strong and 
definite twists. In shape they are flask-like, and exceedingly graceful, 
widening from the stalk into a long body, one of the profiles of which is 
usually more convex than the other. This tapers gradually upwards into a 
distinct neck, which widens slightly again before the truncated termination 
is reached. The aperture is circular and lies at right angles to the long 
axis of the gonangium. Our specimens thus resemble Hartlaub’s more 
closely than they do Hickson and Gravely’s. They bear considerable like- 
ness to the gonangia of Campanularia volubilis, as figured by Hincks 
(1868, pi. xxiv. fig. 2). 
Some of the gonangia contain many much-decomposed ova. The differ- 
ence between these gonangia and those formerly described may be due in 
