Phy l log loss tint Drummondii , Kunze. 317 
perennating tubers, by means of which he was able to trace the development 
of a new tuber, and the origin of the bud enclosed in its free end. 1 A new 
tuber appears first as a projecting mass of tissue with the growing point 
situated in a depression in the centre. The growing point, however, does 
not long maintain its central position, becoming first sunk, and then inverted 
owing to the rapid and unequal growth of surrounding tissue. Finally, it 
takes the form of a conical mass of meristematic tissue at the base of 
a narrow channel. This channel, although less distinct in older specimens, 
never becomes completely obliterated. Its position can generally be recog- 
nized, at least in transverse sections of a 
tuber, by the smaller cells which surround 
it. It had earlier been observed by Bertrand, 
and called the e canal de Braun \ 2 
This protected position of the bud, and 
the fact that by intercalary growth it is carried 
some distance into the substratum, are fea- 
tures showing a marked specialization for a 
geophytic habit. The tuber can, however, 
be regarded also as a means of vegetative 
propagation, since more than one may be 
formed during the season. 3 
In the course of this investigation two 
different collections of material were ex- 
amined — the one which I owe to the kindness 
of Professor F. E. Weiss was obtained from 
New Zealand, the other was made in South- r 
West Australia by Professor Benson in mid- s n 
winter, August 3, 1914. This collection 
consisted of over one hundred plants, about 
one-third of which were fertile, showing Fig. i. 
features similar to those of the specimen 
figured. Many of the sterile plants were very young, bearing only one or 
two leaves, but, like the fertile plants, each possessed one new tuber. The 
New Zealand specimens had evidently been collected later in the season, 
and, moreover, they were on the whole better developed plants. Five were 
exceptionally interesting in that each possessed two new tubers. These 
plants had been set aside by Professor Weiss for further investigation, and 
were with great generosity handed over to me. 
1 Bower : loc. cit, 1886. 2 Bertrand : loc. cit., 1884. 
3 Thomas : Proc. Roy. Soc., 1901-2, p. 290. 
