124 ORCHID ACE AE. 5. Prasophyllum. 



genus reduced to a braot in the flowering season. Flowers several or numerous in a 

 terminal spike, usually inconspicuous in color, commonly greenish, white or purple, 

 sometimes fragrant. 



The genus has representatives in New Zealand, but is otherwise exclusively Australian. 

 About 60 valid species have been recorded. 



Leaf fully developed at time of flowering ; flowers not 

 minute. 

 Lateral sepals connate in the bud and in the freshly- 

 expanded flower. 

 Labellum acutely or abruptly flexed about the middle. 

 Labellum conspicuously white ; callous part pro- 

 minently raised, ending close to the bend ; ovary 



long and very slender P. australe 1. 



Labellum green ; callous part not much raised, 

 ending much beyond the bend : ovary very short 



and turgid P. occidentals 2. 



Labellum not acutely or abruptly flexed ; callous part 

 extending much beyond bend. 

 Plant very tall and robust ; flowers green, sometimes 

 almost black ; labellum not constricted ; callous 



part with free margin P. datum 3. 



Plant slender ; labellum with conspicuous lateral 

 constriction near the tip. callous part raised and 

 ending abruptly beyond the constriction. 

 Flowers usually green, occasionally dark-prune 



colored ; labellum on well-marked claw P. gracile 4. 



Flowers prune -colored ; labellum sessile P. constrictum 5. 



Lateral sepals always free. 



Labellum acutely flexed about the middle. 



Labellum conspicuous^ white ; lateral appendages 



bluntly falcate P. odoratum 6. 



Labellum white, but not conspicuously so : lateral 

 appendages acutely lanceolate with a third 



linear intermediate lobe P. rotundiflorum 7. 



Labellum not acutely flexed. 



Labellum with membranous portion wider than 



callous part P. patens 8. 



Labellum with callous part wider than membranous 

 and reaching nearly to the tip. 

 Flowers green or yellowish -green ; little or no 



perfume P. fu6cum 9. 



Flowers with prune colored labellum ; callus 



velvety ; very powerful odor P. Fifzgeraldii 10. 



Leaf undeveloped at time of flowering or represented only 

 by a small bract. 

 Labellum not ciliate. 



Labellum petals and usually dorsal sepal dark -purple ; 

 former about equal in length to dorsal sepal and 

 narrowing abruptly to a very acute point ; lateral 



sepals green P. nigricans 1 1 . 



Labellum dark reddish-brown, shorter than tbe dorsal 

 sepal, very convex, tip very blunt ; sepals and 



petals green P. fuscomride 12. 



Labellum ciliate deep purple ; other segments yellowish- 

 green with pale-purple linear markings P. intricatum 13. 



1. P. australe (southern). R. Br. Often ^lender, 25-75 cm. high. Leaf -lamina usually 

 shorter than the spike. Flowers sessile, on a very slender terete elongated ovary often 

 upwards of 10 mm. long, in a rather loose spike, sweet-scented, with prevailing tints of 

 white brown and green. Segments of perianth all very acute ; sepals yellowish-green 

 and nearly equal in length ; the dorsal one about 8 mm. long, erect or recurved, concave, 

 ovate -lanceolate ; the lateral ones sometimes free at extreme base, united beyond this 

 almost to the tips. Petals erect, yellowish-green with wide reddish -brown stripe down 

 the centre, narrower and rather shorter than the lateral sepals. Labellum conspicuously 

 white, sessile with bulging erect base ; acutely reflexed about the middle ; the free end 

 voluminous, much crisped, with undulate margins ; callous part ending abruptly in 2 

 much elevated knuckles at the bend. Anther erect, with short point, 2-celled, not so 

 high as rostellum. Lateral appendages lanceolate -falcate, adnate in front to the pedicel 

 of the stigmatic -plate, the basal lobes thickened and sinuous, about equal in height to 

 the rostellum. Viscid disk large, ovate, situated in a triangular depression on the front 



