The Vegetation op Western Australia. 
xlix. 
The heath formation is the real home of tlie true autochthonous flora, 
which is exhibited here in endless variety. The most representative families 
are Epacridaceae, Haemodoraceae, Casuarinaceae, Proteaeeae, Myrtaceae, 
Verbenaceae, Rhamnaceae, and Goodeniaceae. On its broad mosaic pattern 
we are able to delineate with fair exactness the limits of the Epacridaceae, 
and such genera as Anigozanthus, Conostijlis, Drosera, Isopogon, Petrophila, 
Conospermum, Lamhertia, Banksia, the various genera of the Chamaelaucieae, 
Kingia, Xanthorrhoea, CalectasiGy and a large number of plants which re- 
present the autochthonous element. 
Characteristic of tlie heath formations is the development of dew, even 
in the summer. When the formations of tlie heavier soils are quite dry in 
the early morning, a heavy moisture between the months of November and 
March characterises the heaths, even to the limits of the South-West Pro- 
vince. Another characteristic is the erect or erect-spreading ericoid type 
of leaf, and this, together with the erect branching of the shrubs, causing 
an open fabric of the constituents, results in a high insolation. Several plants 
possess, as a protective measure, a strong development of corky tissue at 
the base of the stem. This is particularly noticeable in several species of 
Boronia and Eriostemon. 
In contrast to the plants of the heavier soils, the heath shrubs possess 
very deep rooting systems. It is not uncommon to find shrubs less than 
15 cm. high with a root system extending to a depth of over 60 cm. Most 
of the plants have a strong j)rjmary vertical with deep horizontal secondary 
roots, the tap-root being as a rule remarkably strong, with a fibrous cortex. 
While the contour of the heath vegetation remains more or less uniform, 
a number of sj^ecies usually occur whicli rise much above the general level. 
Several species of GrevUlea, Xylomelum angustijoliu7n, Haken, Banksia, and 
Actinostrobus are familiar examples. They either occur in small groups, 
or may be found in isolation, standing like sentinels on the heath profile. 
Otherwise the heath is very uniform in tlie height of its component shrubs. 
Some of the heatli species, especially the Rhamnaceae and the Epacridaceae 
bloom before the advent of the winter rains, for example, I have seen Leu- 
copogon and Cryptandra in full bloom at the end of April at the end of the 
long dry summer. On the other hand, due perhaps to the beneficial influence 
of the dews, certain heath species bloom in the height of summer. Verti- 
cordia and Co7iosper7mtm are notable in this respect, and it should be re- 
membered tliat the glorious Nuytsia which is so aptly named flo7'ihunda, 
and which flings its golden wealth abroad in both coastal woodland and 
sand-heath, is a true jisammophyte, and most abundant on the low open 
heaths between Esperance and the Oldfield river. 
Amongst the heath plants one observes as in no other formation except 
the swamp-yate woodland, a remarkable development of plagiotropism. 
The most notable examples are the extraordinary species of BaTiksia of the 
series Prostratae which occur all along the southern heaths between King 
George’s Sound and Cape Arid. Their subteri’anean stems radiate to a 
diameter of over four metres, the isolated inflorescences and floral leaves 
of some s]]ecies aj^pearing as isolated plants. Other notable examples are 
the species of Eremophila, Lesche7}avltia, Astrolo7ua, Scaevola^ Hibbertia, 
Acacia, Grevillea thrysoides and G. nudiflora, Dodonaea, and others, including 
several species of Darwinia. 
It is in the lieath formation that the species of the South-West Pro- 
vince exhibit their greatest epharmonic convergence. Species of entirely 
different families may a]q)ear so alike in form and structure as to be indis- 
