of the Australia,/ Flora.] 
1NTR0DUCTO1IY ESSAY. 
The rarity in both of Aroidea, Laurinea, and all Rmtiacem except the Aufhosjarinnv, is also worthy 
of notice. With regard to the Natural Orders enumerated alwve, their genera are almost unexcep- 
tionally different in the two countries. I find that of 1,000 South African genera of flowering plants, 
only about 280 are Australian; of these about ICO are also common to Europe, and 180 to India. 
leaving Callitris, Enapha/artos, Rest 'to, llijpohcna, and Atujitillaria, confined to South Africa and Aus- 
tralia, and 10 more common to these countries, together with New Zealand and extratropieal America. 
On the other hand, South Africa contains upwards of 220 Kuropean genera, of winch SO arc not 
Australian, and of these upwards of GO are north temperate forms. AVc have hence the very curious 
fact that in point of numbers Australia represents genericalU the Kuropean Flora bitter than South 
Africa does j but that the South African Flora contains a larger proportion of very northern European 
genera (not species) than Australia does. This is no doubt because many of the so-called European 
genera of Australia are more properly Asiatic, and spread thence in both directions, towards Europe 
and towards Australia. 
Before dismissing this subject, it is as well to glance at the differences between these Floras, which 
may shortly be summed up. South Africa abounds in Campanulacece, which are very ran- in 
Australia, where the very closely allied Orders ShjHtl'n „■ and Uoot/rnit/rrtc abound. The true Knctie, 
which swarm in certain districts of South Africa, are all but wholly absent in Australia, hem- repre- 
sented there by their suborder Epacridea. Succulents are, comparatively, extremely rare m A .-t. : 
lia, which almost wholly wants those conspicuous features of South African vegetation ' h ' 
FiroidctP, fleshy Asrti jntuhuc, LUlacece (Aloes), and Eitphorbim>. 
I have given (p. xxxiii.) a list of the five Orders which abound more in South Africa than in any 
other country but Australia, and arc therefore highly characteristic of both these. 1 shall now give 
the contrasting ordinal dissimilarities of each. 
The following Orders are represented in the South African Flora, but are either comparatively 
rare or absent in Australia : — 
, absent in Australia, 
ditto. 
Dipsacea?, absent in Australia. 
Arctotideae (tribe of Comp.). 
Campanulaceae. 
Stilbinese (Verben.), absent in Australia. 
Selaginea? (Verben.), ditto. 
Asclepiade®. 
Podostemaceoe, ditto. 
Srarurea, ditto. 
Katia 
>a!\ 
, absent in Australia 
Crassulace®. Hypoxide; 
Talerianeae, 
Temperate Australia contains the following Orders that are rare or absent in Sout 
Dilleniaceae, absent in South Africa. Tremandrea?, absent in South . 
Magnoliaceae, ditto. Pittosporeae. 
MonimiaceaJ. ditto. Stackhousieae, ditto. 
Sapindacea?. Halorageae. 
