74 



APOSTASIA. Bhonc Bydrag. p. 423. 



" Perianthium limbo seApartito, regulari. Stamina antherifera 2, quorum Filamenta foliolls lateralibus in- 

 terlorum perianthil opposita, Infra connata cum basi Styli supra cylindracei, et vel nudi, Vel hinc Filamento 

 TERTio castrato, altiiis adnato, foliolo antico exteriorum opposite, appendiculati. Anther.'e biloculares, longitudi- 

 naliter dehisccntes. Pollen e granulis simplicibus, solutis. Stigma obtusum, obsolete bi-trilobum. Capsula tri- 

 loctilaris, polysperma. Semina ovata, testa nucleo conformi," — Brown MSS. 



Classis Linncana : Gynandria Diandria. 



Ordo naturalis ; Orchidearum Trib. Apostasteoe Br. 



Obs. •' This very remarkable genus, founded on Apostasia odorata, was first published in 1825 by Dr. Blume in the 

 work referred to; but in 1821 a nearly related species was discovered in the valley of Noakote in Nipal, by the 

 plant-collectors of Dr. Wallich, who, in his manuscripts, which I have had the advantage of consulting, named it 

 Mesodactylk dejiexa, and at the same time had the drawing made, which is here given. 



" I have followed these two distinguished botanists in regarding Apostasia as belonging to, or at least as most 

 nearly related to, OrchidecB. It exhibits, however, very few of those characters generally considered as essential to 

 that'family of plants. 



" In its antherae, pollen, style, and stigma (all which parts are so remarkably modified in OrchidecB) Apostasia does 

 not materially differ either in form, structure, or economy, from the more regular-flowered famiHes oi Monocotyledones; 

 and in its trilocular ovarium it is distinguished from all other genera of tlje order to which it is here appended. 



" On the other hand it agrees with Orchideoe in the structure, as far as I am able to ascertain, of its minute seeds ; 

 in the reduced number of stamina, and probably, with some genera of the family, in the order of their reduction ; in 

 the filaments being at base connate with the lower part of the style ; and in a great degree In habit. In endeavouring 

 to estimate the importance of the several points of resemblance and difference here enumerated, with a view to decide 

 on the degree of relationship Apostasia bears to OrchidecB, it Is necessary to consider the relative position of the 

 parts of the flower In that order, and also In Scitaminece, the family most nearly allied to it. 



" The relation of stamina to the ])arts of the floral envelope In Apostasia Is In the first place to be determined. Tlie 

 two antherlferous filaments, which I have more particularly examined in the unexpanded flowers of Apostasia nuda, 

 appear to be opposite to the two lateral segments of the Inner series of the perianthium ; and the sterile filament in 

 Apostasia IFallichii, and no doubt also in A. odorata, is opposite to the anterior segment of its outer series. 



" Several years since I advanced the opinion, 'That in a comjflete flower, whose parts are definite, the number of 

 stamina and also of pistilla is equal to that of the calyx and corolla united in Dicotyledones, and of both series of the 

 perianthium in Monocotyledones* ' 



" It may be further observed, that in cases of reduction of pistilla it is generally found, that the remaining carpella 

 when more than one, but inferior in number to that of one series of the floral envelope, correspond in position with 

 parts of both series, and with very few exceptions, whether distinct or confluent, are all equally developed. Stamina, 

 on the other hand, in cases of equal reduction, generally belong to one of the series only, or. If corresponding with 

 parts of both series, are usually in different states of developement, as they are here described to be in two species of 

 Apostasia. 



" This appearance of part of the inner series of stamina has not hitherto been expressly remarked in Orchidew. It 

 is not improbable, however, that the same relation to perianthium exists In the lateral antherlferous stamina of Cypri- 

 pediwnf, as well as in the sterile petaloid processes similarly situated in other genera, as in Diuris. And the third 

 stamen of the Inner series, still more altered In form, may be considered as present in certain New Holland genera, 

 especially Glossodia, where this supposed stamen is placed within the labellum, but entirely distinct from it; in 

 Epiblema, Pterostylis, and Chihglottis, in which an analogous appendage similarly situated coheres in various 

 degrees with that division of the perianthium ; and perhaps it may be considered as indicated in all cases where the 

 labellum is furnished with a process, however minute, arising from Its axis. 



" If the view here taken of the position of the lateral filaments In Cypripediiim and Diuris be adopted, it may be 

 remarked that indications or rudiments of the two stamina necessary to complete the number in Orchideoe, of those, 

 namely, corresponding with the lateral segments of the outer series of the perianthium, have not yet been observed in 

 the regular structure of any plant of the order. They have however been occasionally met with in monstrous flowers 

 of Hahenaria brfolia. In more than one spike of which I have found the greater number of flowers triandrous, the 

 three antherae being equidistant, and placed exactly opposite to the three divisions of the outer series of the perian- 

 thium, the inner series of which remains in its ordinary state. 



* In 1826, in Appendix to Denham and Clapperton's Travels, p. 1^1. | Prodr. Fl. Nov. HoU. I. p. 309. 



