Antiquity of the Angiosperms — SUESSENGUTH 
Of the seven tribes of the family Protea- 
ceae, the Persoonieae is the most primitive, as 
Engler has stated in his Natilrliche Pflanzen- 
familien ( III / 1 : 127). The Persoonieae are 
found in Australia, Tasmania, New Caledo- 
nia, and, to a lesser extent, in New Zealand. 
One species of Brabeium appears at the Cape 
of Good Hope, but has developed farther 
than its relatives in Australia, as is proved by 
its floral axis which shows a cyathiform ex- 
crescence at the base. In any event, the most 
primitive representatives of the Proteaceae 
are almost completely limited to Australia. 
In the Santalaceae, the members of the 
tribe Antholobeae, with their superior ovary, 
are considered primitive. The genus Antho- 
lobus is native to Australia. A closely related 
genus, Exocarpus, is found in Australia, Nor- 
folk Island, the Malaysian islands, India, 
Madagascar, and Hawaii, although most of 
its species are native to Australia. The 
genus Champereia is found in Malacca and 
the Malaysian archipelago. It can be con- 
cluded, therefore, that the Santalaceae are of 
Australian-Malaysian — that is to say, of post- 
Gondwanesian — origin. 
The most primitive Apocynaceae are those 
in which the stamens are not tightly con- 
nected with their stigma heads. These are 
the Plumieroideae, especially a subgroup of 
them, the Pleiocarpeae, which have apocar- 
pic ovaries, pistils split at the base, and more 
than two carpels. Among them are two 
genera with the primitive arrangement of 
alternate leaves: Notonerium Benth., an eri- 
coid bush growing in southern Australia, and 
Lepinia Decne., a tall tree found in Tahiti. 
The most primitive species of the Apocyna- 
ceae, therefore, are Australian-Pacific in their 
origin. 
It might be noted in passing that this same 
conclusion cannot be drawn for the Asclepia- 
daceae. Here the Periploceae are the most 
primitive forms, judging by their tetrad pol- 
len, the translators of which have no reti- 
nacula; and of these primitive Periploceae, 
297 
the most primitive are those which possess 
no corona, as, for example, the Gymnolaima 
of Kilimanjaro, Africa, the Phyllanthera of 
Java, and the Pent am era of Sumatra. The 
Asclepiadaceae are generally more highly 
evolved than are the Apocynaceae, but they 
do not originate in Australia. 
Let us now go on to consider a rather com- 
plicated group, the Cyperaceae. Here the 
species of Scirpoideae, with their hermaphro- 
ditic flowers, are more primitive than are the 
Caricoideae, the flowers of which are rarely 
hermaphroditic. The nature of the axes in 
the inflorescences of the Caricoideae also 
proves to be a derived feature. Among the 
Scirpoideae there is a tribe, the Hypolytreae, 
whose members have bracted flowers; and 
the transverse arrangement of these bracts 
(as occurs among the Hypolytrinae) might 
be a more primitive characteristic than is the 
possession of one or two median bracts (as 
occurs among the Lipocarphinae ) . Among 
the Hypolytrinae the genus Hypolytrum , 
whose species show free bracts, is most prim- 
itive. A species of Hypolytrum, H. latifolium 
L. C. Rich., is found in Queensland, but it is 
also found in south Asia, Africa, America, 
and Polynesia. Two species of Lipocarpha 
also have an extensive range. The genus 
Hypolytrum has its representatives in the 
tropical and subtropical ranges of both hemis- 
pheres. All of this evidence would seem to 
show that the oldest living types of Cypera- 
ceae — which is considered a rather ' modern” 
family — have their native habitat in the 
tropics, but by no means in Australia. 
In contrast to this, the oldest genus of the 
Scirpoideae-Cyperinae, the genus Carpha R. 
Br. — without disk, but with setaceous involu- 
cre, six setae, and a three-cleft pistil — is repre- 
sented by one species from Australia and 
New Zealand and by another in extra-tropical 
Andean South America. 
In the large subfamily of the Caricoideae, 
the Rhynchosporeae are the most primitive, 
inasmuch as, in most cases, they have three 
