H. F. Wernham. 
148 
The tribe Vaccinioideae, the Vaccinieae of Bentham and Hooker, 
is unique among the Ericales in the character of inferiority of the 
ovary; and on the lines we have laid down, this would appear to 
throw some measure of doubt upon the propriety of associating 
this extensive group so closely with the Ericales. We shall return 
to them shortly; we may remark in the meantime that their 
flowers differ in no essential way from those of the other Ericaceae, 
save in the relative position of the ovary. 
The Ericales, with their double staminal whorl, multilocular 
ovary, and frequent presence of a more or less conspicuous disc, 
seem to have undoubted affinities with the Geraniales. In both 
cohorts the same tendency to reduction in the number of stamens 
and carpels is observable; and in many ways the Geraniales are 
considerably more advanced than the Ericales. For the bicar- 
pellary condition of the ovary is realized in an extensive section, 
viz., Engler’s group D, of the former cohort, which includes the 
large natural order Polygalaceae. The latter, moreover, are 
remarkable for their zygomorphic flowers, and zygomorphy is by no 
means rare among the other orders of Geraniales. The tendency 
to cohesion of filaments, again, has already been referred to as a 
distinguishing feature of this cohort. Lastly, the presence of one 
or two ovules only in each loculus of the ovary, in the large 
majority of the Geraniales, represents a material advance in the 
direction of economy as compared with the Ericales, in which the 
number of ovules is usually indefinite. 
The Ericales, on the other hand, are very distinct and 
specialized both in habit and in habitat; the natural orders and 
larger subordinate groups can be readily recognized, in most cases, 
by the habit alone. That of the tribe Ericoideae is so charac¬ 
teristic as to have given rise to a general botanical term—the 
ericoid or heath habit. The shrubby and arboreal members of the 
other ericaceous tribes, with their typically entire, elliptic, leathery 
leaves tending to a rosette arrangement upon the twigs, are recog¬ 
nizable with little difficulty. The Epacridaceae, again, are mostly 
small shrubs with narrow rigid leaves, representing in Australia 
and Tasmania the Ericaceae of other regions. The low rhizomatous 
growth and small half shrubby, half herbaceous habit of the green¬ 
leaved Pyrolaceae and the alpine and arctic Diapensiaceae, with 
their flowers borne usually in scapes, are clearly distinctive 
features; while the non-green Pyrolaceae (Montropeae) and the 
