„6 NATIVE BRITISH ORCHIDACEyE 



but in Listera this groove secretes honey, and there is a relatively large leaf-like 

 rostellum, whilst in C. innata no honey is secreted there, and the rosteUum is very 

 small. Both are founded on the idea of leading the insect up to a definite point (the 

 angle where the lip bends) where it is bound to come in contact with the rostellum. 



Tribe III EpiPOGONEiE Parlatore 



Stigma on projecting foot of column; rostellum heart-shaped. Pollinia pear- 

 shaped, compact, dependent on long caudicles arising from base of polHnium 

 and running up to its apex. Subterranean plants with coralloid rhizome emitting 

 runners but no roots, without leaves or chlorophyll, and with large non-reversed 

 flowers. Only one genus and one species. 



Epipogon was considered as a species oiSatyrmm by Linnasus, oiEpipactls by Crantz, 

 and of Umodorum by Swartz. It has been assigned to the Arethuseie by Reichenbach f., 

 the Gastrodie^ by Lindley, and the Neottieas by various authors. It really stands 

 alone, and forms a tribe of itself. The following characters are peculiar— the large 

 inverted spur, the downward-facing stigma on the overhanging base of the column, 

 the large rostellum with its cordate viscidium in a V-shaped incision at the apex of 

 the column, and the suspension of the pollinia on long elastic caudicles. 



Genus XI EPIPOGON Rich. 



Flowers pendent, non-reversed, lip uppermost, sharply bent upwards in the middle, 

 with a rounded lobe on each side, mid-lobe cordate, erect, with tubercled ridges. 

 Spur inflated, erect. Column pointing downwards with overhanging base, on which 

 is the stigma, and a deep clinandrium at the apex. Anther non-deciduous. Pollinia 

 two, pear-shaped, caudicles flat, ruiming up from base nearly to summit. Pollen- 

 grains in tetrads bound together by elastic threads. Rostellum large, heart-shaped. 

 Saprophytic subterranean plants without chlorophyll, only the flower-stem appearing 

 above ground, often at intervals of several years. Rhizome branched, coral-hke, 

 emitting thread-like runners. 



Epipogon Rich., Mem. Mus. Paris, iv, 42, 5° (1818). Epipogum Gmelin, 

 F/. Sibir. I, t. 272 (1747). 



