Natural Orders .] 
APPENDIX. 
545 
The Tremandre* are in several respects nearly related to Poly gale* ; 
they appear to me however sufficiently distinct, not only in the regularity 
of the flower, and in the structure of antherse, but in the aestivation of both 
calyx and corolla, in the appendix of the seed being situated at its apex, 
and not at the umbilicus, and, I may also add, in a tendency to produce 
an indefinite number of ovula in each cell of the ovarium. 
The greater number of Tremandreae are found in the principal parallel 
of New Holland, ‘they extend also to the south end of Van Diemen’s Island, 
but none have been observed within the tropic. 
DlOSMEdE. To this natural order, in addition to the Australian 
genera hereafter to be mentioned, and the south African genus from which 
its name is derived, I refer Fagara, Zanthoxylon, Melicope, Jambolifera, 
Euodia, Pilocarpus, Empleurum, and Dictarnnus : and four genera of sequi- 
noctial America, namely, Cusparia of Humboldt and Bonpland, Ticorea 
and Galipea of Aublet, and Monnieria, if not absolutely of this order, 
belong at least to the same natural class. 
Both Ruta and Peganum may be annexed to Diosmeae, but neither of 
them are calculated to give a clear idea of the order, from the usual struc- 
ture and habit of which they deviate in some important points ; I have there- 
fore proposed to derive the name of the family from one of its most extensive 
and best known genera. The first section of Jussieu’s Rutaceae is sufficiently 
different to admit of its being considered a distinct order, which may be 
named Zygophylle*. 
Diosmeae are numerous in Terra Australis, and form, at least in its 
principal parallel and more southern regions, a striking feature in the vege- 
tation. Nearly 70 species have been observed, of which the greater part 
are referable to Boronia, Correa, Eriostemon, and Zieria, of Dr. Smith, and 
Phebaliurn of Ventenat. Of these genera Boronia is both the most exten- 
sive and the most widely diffused, existing within the tropic, and extending 
to the South end of Van Diemen’** Island ; like the others, however, its 
maximum is in the principal parallel, at both extremities of which it is 
equally abundant. Correa, though extending to the south end of Van 
Diemen’s Island, is not found within the tropic, nor was it observed at the 
western extremity of the principal parallel ; in the intermediate part of 
4 A 
yon. ij, 
