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CCXL. ORCHIDE.'E. The Orchis Tribe. 



Orchides, Juss. Gen. 64. (1789)._Orchide/F., R.Brown Prorfr. 309. (1810) ; Rich. 

 in Mim. Miis. 4. 23. (1818), Lindl. Synops. 250. (1829); Id. Genera and Species 

 o/OrcA. (1830.) 



Diagnosis. Gynandrous monocotyledons, with 3 pafietal placenta?. 

 Anomalies. Apostasia, if belonging to the order, has a trilocular ova- 

 rium and distinct stamens. 



Essential Character — Periuntldum superior, ringeut. Sepals 3, usually coloured, 

 of whicli the odd one is uppermost in consequence of a twisting of the ovarium. Petals 3, 

 usually coloured, of which 2 are uppermost in conseijuence of the twisting of the ovarium, 

 and 1, called the lip, undermost ; this latter is frequently lohed, of a different form from the 

 others, and very often spurred at the base. Stamens 3, united in a central column, the 2 

 lateral usually abortive, the central perfect, or the central abortive, and the 2 lateral perfect; 

 anther either persistent or deciduous, 2- or 4- or 8-celled ; pollen either powdery, or coher- 

 ing in definite or indefinite waxy masses, either constantly adhering to a gland or becoming 

 loose in their cells. Ovarium 1 -celled, with 3 parietal placenta; ; style forming part of the 

 column of the stamens; stigma a viscid space in front of the colunm, communicating directly 

 with the ovarium by a distinct open canal. Impregnation taking effect by absorption from 

 the pollen masses through the gland into the stigmatic canal. Capsule inferior, bursting 

 with 3 valves and 3 ribs, very rarely baccate. Seeds parietal, very numerous ; testa loose, 

 reticulated, contracted at each end, except in one or two genera ; albumen none ; embryo a 



solid, undivided, fleshy mass Herbaceous plants, either destitute of a stem, or forming a 



kind of above-ground tuber (pseudo-bulbus) by the cohesion of the bases of the leaves, or 

 truly caulescent. Roots in the herbaceous species fleshy, divided or undivided, or fasciculate ; 

 in the caulescent species tortuous, and green and proceeding from the stem. Leaves simple, 

 quite entire, often articulated with the stem. Pubescence rare ; when present, sometimes 

 glandular. Flowers in terminal or radipal spikes, racemes, or panicles ; sometimes solitary. 



ApFiisriTiES. It is not necessary to enter, in this place, into an historical 

 inquiry as to the gradual alteration that has taken place in the views of 

 botanists with regard to the structure of the sexual apparatus of these 

 most curious of plants, or to explain what degree of error existed in 

 the descriptions of those who mistook masses of pollen for anthers, or a 

 column of stamens for a style : such errors could only have occurred at 

 a period when the laws of organisation were totally unknown. They have 

 been corrected, in a more or less perfect manner, by various writers ; most 

 completely by Mr. Brown in his Prodromus, published in 1810, and subse- 

 quently by the late most accurate and indefatigable Richard. But long 

 before the publication of any rational explanation of the structure of the 

 Orchis tribe, while botanists were in utter darkness upon the subject, it had 

 been most fully investigated by a gentleman unrivalled for the perfection of 

 his microscopical analyses, the beauty of his drawings, and the admirable 

 skill with which he follows Nature in her most secret workings ; and let 

 me add, which is a still rarer quality, the generous disinterestedness with 

 which he communicates to his friends the result of his patient and silent 

 labours. I have sketches before me by Mr. Bauer, executed from 1794 to 1807, 

 in which not only all that has been published since that period is shewn in 

 the most distinct and satisfactory manner, but in which much more is repre- 

 sented than botanists are even now aware of. I hope to be the humble 

 means of giving some of these extraordinary productions of the pencil to the 

 world, in an illustration of the Genera and Species of Orchideous Plants, which 

 is now in preparation. If the sexual apparatus of an Orchideous plant is 

 examined, it will be found to consist of a Heshy body stationed opposite the 

 labellum, bearing a solitary anther at its apex, and having in front a viscid 

 cavity, upon the upper edge of which there is often a slight callosity. This 

 cavity is the stigma, and the callosity is the point through which the ferti- 

 lising matter of the pollen passes into the tissue counnunicating with the 



