Callitris of Ventenat[1] is peculiar to Terra Australis, where it exists very generally, but most abundantly in the principal parallel: it consists of several species, differing from each other chiefly in the form of their fruit.
Araucaria excelsa, which was first observed in Norfolk Island and New Caledonia, is found also on the east coast of New Holland, immediately within the tropic: it is there, however, a tree of very moderate dimensions, and never of that enormous size which it not unfrequently attains in Norfolk Island.
ORCHIDEÆ.[2] The Australian species of this order already known amount to 120, many of these, however, are of very rare occurrence, and none of them appear to be produced in abundance.
The maximum of the order exists in the principal parallel, a considerable part extends to Van Diemen's Island, and very few have been observed within the tropic.
The greater part form genera nearly or entirely peculiar to Terra Australis, and most of these genera belong to that division of the order having farinaceous pollen, with an anthera which is inserted but not deciduous, and either parallel to the stigma or terminating the column. The two sections of this division with parallel and terminal anthera, are found in New Holland to pass very gradually into each other, and several genera belonging to the former are, in that country, remarkable for the great expansion of the lateral lobes of the column. These lateral lobes I have considered as barren stamina, which, like those of Philydrum, are occasionally, though indeed very rarely, furnished with rudiments of Antheræ. This structure as well as that of Cypripedium, in which the lateral lobes are antheriferous, while the middle is barren, approximates the flower of Orchideæ to what may be called the type of Monocotyledones, that is, a regular flower with ternary division of its envelope, stamina, and cells or placental of the fruit.
I have attempted a similar approximation of true Scitamineæ,[3] whose processes crowning the ovarium, and usually two in number, form the complement of the stamina.
