22 
Proceedings of the Royal Society of Edinburgh. 
[Sess. 
Campanularia volubilis (Linnaeus), var. antarctica, nov. 
Trophosome . — Springing from a creeping stolon which is for the 
greater part smooth, although lengths here and there show strongly 
marked twists, are closely set hydrocauli and gonangia. A hydrocaulus 
is generally straight, with a diameter about half that of the stolon, marked 
by a few (three to five) twists at the base, which die away, leaving the 
remainder of the perisarc smooth. Rarely do additional undulations appear 
Fig. 6 . — Campanularia volubilis, var. antarctica , trophosome and gonangia. The gonangium 
on the right shows an abnormal constriction, x 15. 
on the outline of the hydrocaulus except where a stalk has been truncated 
and a new portion, which possesses the usual basal twists, has been re- 
generated from the place. 
The hydrothecae are of the volubilis type, twice as deep as wide, with 
walls that, in profile, scarcely diverge from each other, and with ten to 
thirteen rounded marginal teeth. The hydrotheca has a prolonged base, 
from which it is separated by a diaphragm, and which rests upon a very 
definite spherical internode intervening between hydrotheca and hydrocaulus. 
The hydrothecae are slightly attached and in most cases have been broken off. 
Gonosome . — Gonangia spring abundantly from the stolon. They are 
large and flask-shaped, gradually widening from below to a median 
