lx. 
Charles Austin- Gardner. 
felt or hair, or only to a very slight extent. It reaches its epharmonic climax 
when complete aphylly is secured, as in Casuarina and Acacia, and the genista- 
like forms of Eremophila scoparia and Calycopeplus Helmsii. 
Occasionally in the mulga-bush we find a different growth-form adapted to 
withstand the action of dry winds. This is the ereot -stemmed, horizontally 
branched form which is typical of Acacias of the A, Grashyi and A. sihirica 
type. The simple stem is widely branched with horizontal branches which 
are again repeatedly horizontally branched to form fiat superimposed layers. 
The lateral outline is thus a series of horizontal planes of leafy twigs bearing 
short erect pine-like foliage. It employs less w’ood than the infundibular type 
because of the superimposition of permanent leafy strata, and it is curious 
that it should be so rare in trees and shrubs of the arid areas. In both this 
and the infundibular form, the branchlets are abbreviated, a character common 
to all the w^oody plants of the dry areas. 
Wliile the infundibular grow’th form leads ultimately to leaf-reduction 
or even complete aphylly in its epharmonic development, the widely branched 
plants of the Eremea retain their leaves in an unmodified condition. The 
I^inoid leaves usually arise from abbreviated axes and are thus fasciculated, 
while the broad-leaved plants have relatively long internodes. Such plants 
retain their comparatively large leaf area by the production of a protective 
covering of felt-like hairs, densely interlocked stellate hairs, or the provision 
of a viscid superficial layer of resinous material. No genus so typically affords 
examples of all types as does the genus Eremophila. In the section Pholidia 
w’e have ericoid leaves ; in Eremocosmos there is a tendency for the branchlets 
to assume the function of leaves, resulting almost in complete aphylly in 
E. Dempsteri ; in the -Sect. Eriocalyx we have flat leaves covered with felted 
hairs, e.g., E. leucophylla, while in Platychilus we have large leaves covered with 
a lacquer of resinous material, as in E. viscida and E. Fraseri, while in the 
Section Stenochilus all types are represented. A similar condition may be 
seen also in Cassia, C. Chatelainiana, C. phyllodinia and C. eremophila, C. 
desolata, and C. glutmosa respectively exhibiting the same forms. 
There is one outstanding example in the Eremea of a tree that does not 
conform to the general epharmonic pattern. This is the Kurrajong (Brachy- 
chiton Gregorii), wdiich maintains a dense bushy crown of bright green soft 
leaves which appear to be unaffected by climatic extremes. In this respect 
it stands in the Eremea as an alien whose relatives populate the monsoon 
wnodland, and its appearance here is certainly strange. It owes its capacity 
to withstand the aridity because of its water-storing trunk, and its ability 
to become deciduous in adverse seasons, being the only tree of its kind within 
tlie Eremean Province. 
The Proteaceae stand in striking contrast to the Myrtaceae and Mimosa- 
ceae in that their growdh form is never infundibular, and rarely even corymbose. 
Isopogon and Petrophila, for example, produce their new shoots close under the 
terminal inflorescence, resulting in a di- or trichotomous system, the old 
terminal infructescences becoming lateral, or remaining in the forks of the 
branches. Occasionally the growdh is sympodially developed. Banksia and 
■ Dryandra also illustrate this form. 
In distinction to this is the remarkable further development of the stem 
or branch found m certain iVIyrtaceae. In Callisteyyioyi, Beaufortia, Calo- 
thamnus, and Regelia, for example, the inflorescence is apparently terminal, 
but the rhachis of the spike continues the vegetative growth w'hich is often 
already w^ell developed before flowering is completed, and branching usually 
occurs imyyiediately above the inflorescence, and is usually verticillate ; the 
