Floristik, Geographie, Systematik etc. 121 
Forrestii from Blackwood River, W. A., named after the collector 
J. Forrest; one of the poison-bushes intermediate between G. velu- 
tinum and G. bilobum. Helipterum album from Wooroloo, W. A., it 
differs from H. pygmaeum , H. corymbißorum var. microglossa, H. 
polyphyllum and H. corymbosum. Podocoma nana , Mount Lyndhurst, 
S. Australia (M. Koch), Torrens Plain, S. A., R. Tate, 1893; its 
closest affinity is with P. cuneifolia. Ptilotus Kennediae, F. v. M. 
(inedit.) from Tandarlo, via Wilcannia, N. S. W. Salicornea Donald- 
sonij and S. Lylei from Cowcowing, W. A. Zygophyllum ovatum 
from the Watheroo rabbit fence, W. A.; it is nearest to Z. ammo- 
phyllum. b. New varieties: Eremophila Woollsiana, F. v. M., var. 
dentata, Cowcowing Lakes, W. Australia. Helipterum heteranthum, 
Turcz. var. minor, Cowcowing, W. A. Isotropis atropuvpurea, F. v. M., 
var. alba, Lake Austin, W. A. New records are: Danthonia airoides, 
Nees; this grass (identified by Prof. Hackel) is hitherto known only 
from South Africa, but it has now been discovered by F. A. Rod- 
way at Soak Creek, W. A. Diplachne loliiformis, F. v. M., is now 
recorded for W. A. (F. A. Rodway, Malcolm). Pterostylis reßexa, 
R. ‘Br., together with some others. The paper contains notes on: 
Bertya oleaefolia, Planch., syn. B. Mitchelli; it is shown that the two 
species do not appear to differ in any constant feature of specific 
rank and can scarcelv be recognised as varieties. Rhagodia spines- 
cens, R. Br. is shown to be a variety of R. crassifolia, R. Br. and 
Kochia Atkinsiana, W. V. F The paper contains some critical notes 
on rare and otherwise interesting plants, chiefly from Western 
Australia. It concludes with some records of introduced plants, 
together with notes on erroneous records of naturalised aliens. 
J. H. Maiden. 
Groom, P., Longitudinal Symmetry in Phanerogamia. (Phil. 
Trans. Roy. Soc. Lond. B. p. 57—115. 1908.) 
The method employed in this work is as follows: Measurements 
of the successive internodes of a stem are made, and are recorded 
on squared paper as successive ordinates; the resultant curve is 
termed the internode curve. The longitudinal distanees apart of other 
members are dealt with in the same manner, and ranged into other 
curves. In a typical herb, the internode curve of the main axis is 
a regulär and characteristic ascending-descending one while those 
of the successive branches, commencing at the base of the plants 
and ascending the main stem, gradually change from the ascending- 
descending curve to a purely descending one or tend to do so. It 
is this gradual change in the internode curve of the successive bran¬ 
ches that explains the two maxima in the internode lengths met 
with in branches. Alternate-leaved Chenopodiaceae, both in the main 
axis and in the branches, display a periodic zig-zag in the internode 
curve. By connecting the alternate ordinates, this can be analysed 
into two consistent and often regulär sub-curves; one of these sub- 
curves is the “internode sub-curve'\ and the other the “displacement 
sub-curve.” By comparison of the curves of the main axis and bran¬ 
ches of Chenopodiaceae and typical herbs, also between those of 
alternate-leaved and opposite-leaved Chenopodiaceae, as well as by 
other means, it is shown that the displacement sub-curve represents 
the distanees up which one leaf at each successive node has been 
relatively displaced from a primitively opposite arrangement. Both 
sub-curves of the main axis assume the ascending-descending form, 
