506 PART IV. CLASSIFICATION. 



England : it has a creeping rhizome and broad ovate leaves : the perianth 

 is of a reddish-brown colour, except the labellum which is yellow and 

 forms a shoe-like sac (Figs. 315, 318). 



MONAXDR.E : one fertile stamen, the anterior, belonging to the outer 

 whorl : only the two lateral lobes of the stigma are susceptible of pollina- 

 tion : the anterior lobe is rudimentary, or is developed as the rostellum: 

 pollen-grains coherent into pollinia. 



Fam. 2. Ophrydince : anther short and broad ; the waxy pollinia are 

 basitonous; a rostellum, forming retinacula to which, the caudicles of the 

 pollinia adhere. 



To the sub-family Serapiadece, which is characterized by the short 

 gynostemium and the erect anther belong the genera Ophrys, Orchis, and 

 Aceras. In Ophrys there are two distinct bursicul^ and retinacula, and 

 the pollinia remain distinct : the flowers resemble insects : 0. apifera the 

 Bee Orchis, 0. aranifera the Spider Orchis, and 0. musciferathe Fly Orchis, 

 occur in chalk pastures. In Orchis there is but one bursicula, but there 

 are two retinacula, so the pollinia may be removed separately, and the 

 labellum is spurred : Orchis Morio, mascula, and militaris, have round or 

 oval tubers ; whilst O. latifolia, maculata, and pyramidalis have palmate 

 tubers. In Aceras (Aceras anthropophora is the green Man-Orchis) the 

 3-lobed lip is not spurred, and there is but one retinaculum. 



To the sub-family Gymnadeniece, characterized by the absence of a 

 bursicula, and consequently bare retinacula, belong the British genera 

 Gymnadenia, Habenaria, Neotinea, Herminium (as also other interesting 

 European genera, such as Chamseorchis and Nigritella). In Gymnadenia 

 (O. Conopsea, the fragrant Orchis) the retinacula are contiguous : in Habe- 

 naria (H. albida, lifolia, viridis, Butterfly Orchis) the retinacula are 

 distant : in Neotinea (N. intacta) the pink perianth-segments are con- 

 nivent: whilst in the preceding genera the labellum is spurred, it is not 

 spurred in Herminium (H. Monorchis, the green Musk Orchis). 



Fam. 3. Neotliince, : pollinia usually soft and granular, either acrotonous 

 or altogether without caudicles. 



To the sub-family Cephalantherece., in which the labellum is transversely 

 segmented, belong the genera Cephalanthera, Epipactis, and Epipogum. 

 Cephalanthera (C. grandijiora, C. enzifolia, C. rubra) and Epipactis (E. 

 latifolia and E. palustris), the Helleborines, are rhizomatous leafy plants 

 with well-developed leaves on the peduncles : the labellum is not spurred, 

 and the rostellum is rudimentary. Epipogum Gmelini is a saprophyte, has 

 no roots, and its leaves are scaly and not green ; it has granular pollinia 

 with acrotonous caudicles, a rostellum producing a retinaculum, and a 

 spurred labellum ; the flower is not resupinate. 



To the sub-family Spirantliece, characterized by a rostellum as long as 

 the anther, producing a retinaculum to which the granular pollinia 

 (without caudicles) adhere, belong the genera Spiranthes, Listera, and 

 Neottia. Spiranthes, Lady's tresses (8. autumnalis, cestivalis, and gemmi- 

 para) has a spike unilateral by torsion, perianth-segments connivent, no 

 spur. Listera, Tway-blade (L. cordata and ovata), has only two foliage- 

 leaves, and spreading perianth-segments, no spur. Neottia Nidus-Avis, the 



