1912-13.] Hydroids of British Antarctic Expedition, 1908. 25 
Distribution. — Gampanulina belgicce is known only from the 
Antarctic: various stations between 70° and 71° 19' S. lat., and 80° to 
89° 14' W. long. (Hartlaub, 1904); M‘Murdo Bay (Hickson and Gravely, 
1907); Gauss Station (Vanhoffen, 1909). 
It seems to me that the characters of the trophosome of Hickson and 
Gravely s Gampanulina A fall within the range of variation of Gam- 
panulina belgicce , with which species I therefore range it. 
Lafoeina longitheca, Jaderholm. 
Lafoeina longitheca , Jaderholm, 1904, p. 4; and 1905, p. 20, pi. viii. figs. 1 and 2. 
Idem , Hickson and Gravely, 1907, p. 29, pi. iv. fig. 31. 
Jaderholm distinguishes his sub-antarctic species from the sub-arctic 
Lafoeina tenuis of Sars, to which it is most closely related, on account of 
the narrower and very long tube-shaped hydrothecse, furnished with a 
markedly everted aperture margin, and also on account of the very short 
sarcothecse of the former. Specimens which I assign to Jaderholm’s species 
modify these distinctions and bring the Antarctic form into even more 
apparent affinity with the Arctic. 
The hydrothecae of the examples collected by the Nimrod are much 
shorter than the average length given by Jaderholm, and on the contrary 
are wider than his examples. In these points they agree rather with the 
specimens obtained by the Discovery , as the following table shows. The 
proportions of both sets, however, fall practically within the limits of 
variation recorded by Jaderholm. On the other hand, Jaderholm emphasises 
the shortness of the sarcothecae of Lafoeina longitheca as compared with 
those of Lafoeina tenuis , and his figures and measurements are con- 
firmed by those of Hickson and Gravely. In the specimens before me, 
however, the sarcothecae are not of uniform height, and are in general 
much longer, their height, in some cases, almost equalling that of the 
neighbouring hydrothecae. And, judging from Sars’s figures, it occasion- 
ally transcends even that of the exceptionally lengthy sarcothecae of 
Lafoeina tenuis. 
The distinction between the two species is less evident than was 
supposed, but I still consider them distinct, on account of the shape and 
dimensions of the hydrotheca, which in Lafoeina longitheca is longer ( cf . 
measurements below), has an everted margin round the aperture, and lacks 
the strong and abrupt constriction that separates the base of the hydrotheca 
of Lafoeina tenuis from the stolon, having instead a gradually narrowing 
basal portion ornamented by five or six spiral twists. 
The gonosome was not observed. 
