174 



ORCHIDACEyE. 



[Endogens. 



next the axis ; occasionally surrounded by a calyculus (or true calyx). Petals (which 

 are to be regarded as sterile stamens) usually 3 ; very rarely one only, placed between 

 the sepals: the lateral usually similar to the dorsal sepal; the third called the lip 

 (labellum), usually larger than the petals, and quite unlike them m form ; horned or hir- 

 nished with various appendages, free or adherent to some other body, occasionally 

 moveable as if spontaneously ; now and 

 then contracted so as to form two separate 

 parts, of which the lowest is called the 

 hj'pocliil, the highest the epichil, and the 

 middle one the mesochil; sometimes fur- 

 nished with a single or double appendage, 

 derived from the stigma. Column consist- 

 ing of the stamens and style consohdated 

 into a central body, so that the latter stands 

 next the lip and the former next the dorsal 

 sepal, sometimes petaloid, and occasionally 

 extended far beyond the perianth (corym- 

 bis). Stamens"^ 3, opposite the sepals, 

 the central only being perfect, except m 

 C^'pripedium, when the central is abortive 

 and the two lateral perfect ; anthers occa- 

 sionally one-celled ; usually two-celled, with 

 the cells separated by 2 or 4 partitions ; 

 standing erect at the end of the column, or 

 turned down flat upon it, or altogether dor- 

 sal ; poUen powdery, or collected into 

 grains, or adliering in wedges tied together 

 by an elastic material, or consohdated into 

 masses of a waxy texture and fixed num- 

 ber, the masses either free or adhering by 

 a caudicle to a gland belonging to the apex 

 (or rostellum) of the stigma. Ovary adher- 

 ent, 1 -celled, composed of 6 carpels, of 

 which 3, opposite the petals, have did;^-mous 

 polyspermous parietal placentee without 

 stigmas, and 3 opposite the sepals have as 

 many stigmas but no placentae; style never 

 distmct, except in Cypripedium and some 

 Neottiese ; stigmas usually confluent in a 

 hollow (or prominent) mucous disk ; the 

 dorsal stigma having on the upper edge 



one or two glands, which are separate in Vandese and Neotteee ; often extended into a 

 beak (rostellum), or hollowed out into pouches, or sometimes di-awn out into 2 parallel 

 or diverging arms ; the lateral stigmas usually obsolete, but sometimes united to the 

 base of the lip in the form of an appendage or pair of plates. Capsule very rarely fleshy, 

 indehiscent and pod-shaped, usually breaking up into 6 dry woody rigid valves with 

 horizontal cells, of which 3 only bear seeds. Seeds innumerable, very minute, with a loose 

 netted skin, very rarely with a hard crustaceous one, sometimes expanded into a circular 

 wmg ; embryo solid, fleshy, without albumen ; chalaza at the apex of the seed, and 

 therefore the radicle next the hilum. 



The general structure of Orcliids, briefly embodied in the foregoing description, 

 has been treated of at such length m the prefatory matter of the Illmtrations of Orchi- 

 daceous Plants, that it is unnecessary to do more than refer the reader to that work. 

 I must, however, take the opportunity of correcting one part of the theoretical view 

 which was there taken of the structure of the column. While, in common with Dr. 

 Brown, I regarded the stigma as really consisting of three parts, usually in a state of 

 confluence, I also supposed the position of the stigmata to be opposite the petals ; being 

 led to that conclusion by the constant position of the stigmatic arms of Ophrydse. That 

 opinion I afterwards retracted, in consequence of the position of the stigmas in C}-pri- 

 pedium, wliich C. spectabile shows most clearly to be opposite the sepals ; and therefore 

 the stigmatic arms of Ophrydae are to be understood as side lobes of that stigma which 

 is opposite the dorsal sepal. This circumstance, however, only confirms the accuracy 



CXIX. 



Fig. CXIX.— 1. Column of Arethusa ; 2. of Stenoihynchus ; .3. of Brassia maculata ; 4. of Orchis 

 mascula ; 6. section of capsule of Ophrys apifera ; 6. seed of Ophrys ; 7. of Pterygodium atratura ; 8. of 

 Vanilla aromatica. 



