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CCXL. ORCHIDE.E. The Orchis Tribe. 



Ohchides, Juss. Gen. 64. (1789).— Orchideje, 7?. Brown Prodr. 309. (1810); Rich, in Mem. 

 Mus. 4.23. (1818); Lindl. Synops. 256. (1829); Id. Genera and Species of Orck. (1830.) 



Diagnosis. Gynandrous monocotyledons, with 3 parietal placentae. 

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

 and distinct stamens. 



Essential Character. Perianthium superior, ringent, Sepals 3, usually coloured, of 

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

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

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

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

 ral usually abortive, the central perfect, or the central abortive, and the 2 lateral perfect ; an- 

 ther either persistent or deciduous, 2- or 4- or 8-celled ; pollen either powdery, or cohering- 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 column, 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, con- 

 tracted 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-bulbous) 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 spe- 

 cies tortuous, and green and proceeding from the stem. Leaves simple, quite entire, often ar- 

 ticulated with the stem. Pubescence rare ; when present, sometimes glandular. Flowers 

 in terminal or radical spikes, racemes, or panicles; sometimes solitary. 



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

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

 wi h regard to the structure of the gy nandro us apparatus of these most cu- 

 rious 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 or- 

 ganization were totally unknown. They have been corrected in a more or less 

 perfect manner, by various writers ; most completely by Mr. Brown in his Pro- 

 dromus, published in 1810, and subsequently by the late most accurate and 

 indefatigable Richard. But long before the publication of any rational expla- 

 nation of the structure of the Orchis tribe, while botanists were in utter dark- 

 ness upon the subject, it had been most fully investigated by a gentleman unri- 

 valled for the perfection of his microscopical analyses, the beauty of his draw- 

 ings, 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 disinter- 

 estedness 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 

 shown in the most distinct and satisfactory manner, but in which 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 gynandrous apparatus of an Orchideous plant is examined, 

 it will be found to consist of a fleshy 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 fertilizing matter of the 

 pollen passes into the tissue communicating with the ovules. Hence such a 

 plant would appear to be monandrous ; it will be seen, however, in Scitamineae 

 and Marantaceee, the only other monandrous orders of Monocotyledons, that, 



