Page:A Voyage to Terra Australis Volume 2.djvu/580

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566
APPENDIX.
[Botany of Terra Australis.

as the tropic. Prostanthera is remarkable in the appendages to its antheræ, in the texture of its fruit, and in the remains of Albumen exiting in the ripe seeds of several of its species. Westringia, and its related genera Microcorys and Hemigenia, differ from the rest of the order in having verticillate leaves, and from the greater part in the structure of antheræ, particularly in the order in which these organs become abortive. Westringia, according to Dr. Smith, has resupinate corolla, a term which in this case cannot allude to a mere inversion in the form of its lips, for this does not exist; and if it mean an absolute change in the relation of its parts to those of the calyx or to the included organs, it cannot, I apprehend, be admitted either in this genus or in any other of the order. The fact which I formerly stated[1] against the resupination of corolla in Labiatæ is the uniformity of its æstivation in this order, in which the upper lip always covers the lower. To those who do not consider this as a sufficient proof, the following, drawn from another equally uniform point of structure, may perhaps appear more satisfactory. In Labiatæ, as well as in several other orders with irregular flowers, the deviation from the usual quinary division of calyx and corolla in Dicotyledones, does not consist in an absolute suppression of parts, but merely in their confluence; a fact indicated by the disposition of vessels; thus, the upper lip of the corolla, which in this order generally consists of one piece, either entire, or more or less deeply bifid, is always furnished with two longitudinal nerves equidistant from its axis, which is without vessels; while each of the three laciniæ usually forming the lower lip, has a single nerve passing through its axis; the upper lip is therefore to be considered even when entire, as made up of two confluent laciniæ: and if this test be allowed to be conclusive, and applied to the corolla of those genera of Labiatæ in which it is supposed to be resupinate, the opinion will be found to be erroneous.

MYOPORINÆ.[2] The principal characters in the fructification of this order, by which it is distinguished from Verbenaceæ, are the presence of Albumen in the ripe seed, and the direction of the Embryo, whose radicule always points towards the apex of the fruit. The first of these characters, however, is not absolute, and neither of them can be ascertained
  1. Prodr. fl. nov. holl. 499.
  2. Prodr. fl. nov. holl. 514.