POLYSTACIIYA. 



ORCniDES. 639 



Peruvia subaiKiina in arborum ramis sylvarum Pdiiiorum. Jan. 1830. (Ciiciiero), 

 I'u|ipig ! Ex parvulis ! (Juxla l\ pos). 

 6. POLYSTACHYA 2EYLAN1CA Liridi. Cot. Rc>g. XXiV. (1838). Misc. 144: 



Caiile.^cen?, foliis oblonpo-lanceolatis, panicula racemosa rannis elon- 



galis, flonbus glaJDris, sepalonim basi Irianrulari , labelli lobo medio ro- 



lundato apiculalo disco hirfuraceo in medio nudo calloso, capsula inter 

 coslas reticulala, 



Demlrobium polystachyum Tliouars 0. Afr. 

 In botli iliese plants the disii ol' ihe labelium is covered wiili a fine frost-iiI(e 

 mealiness ; whidi is removed by ihe lenst tonch. This meallness is a curious mo- 

 dification of ihe hairs found in oiher plonts. When undislurbed it consists of ihreads 

 wiih egg-sl)apedjoints, whicli are filled ^viih air; the surface of eoch joint is mari«ed with 

 wovy oliiique striae, oiicl the interior uniformly contains a nucleus , to which ihere 

 appears to belor;g a circulating apparatus of the same nature , as ihat in Ihe hairs 

 of Tradescanlia and other plants. I have not however succeeded in actually observing 

 any circulalion. But ihe slightest toucb sufflces to deslroy the cohesion between 

 ihe joinls of ihese singular necldace-shaped bodies , so tbat wben tbey are placed on 

 ibe ficld of the niicroscope tbe latier appeors as if covered wiih the eggs of some 

 insect: it is only. wben they are removed from Ihe labellum wiih grcat care, ihat 

 iheir real arliculated siructuie, and iheir analogy wilh such hairs as those; of Tra- 

 descamia is made out. 



Ohs. Huc forsan Polystacbya luleola Hook.? Ex II. 103 (1825). — Defi- 

 nienda P. Ze-ylanica: labelli medio trifidi laciniis lateralibus aculangulis, 

 lacinia antica semiovata lobulafa, menlo triangulo oblusato. l\. fll. 



7. POLYSTACHYA LUTEOLA Lindl. Coll. Bot. 20. (an Hook. Ex. IL 103?). 



Labelli angusli laciniis laleralibus denliformibus abbreviatis, lacinia 

 antica seniio\ala crispula, toto disco inultifurluiaceo , linea elongata 

 callosa per medium, mento oblusangulo. — Haec est vulgatissima in 

 Antillis, Surinamo etc. Rchb. fil. 



Videiur omnino Lindleyana Coll. Bol. 20. (1821). Perafflnis est Polysiachyae zey- 

 lanicae, quae eget jiigo illo characterislico carinaio et gaudet labeilo latiori . lacinia 

 antica breviori. 



rolijstachyn luteola Hook. Focke Ti.lscb. Wis. Nat. Walsch. 203 : 



Heiba epipbyia caulescens. Caulis basi incrassalus ibique callosus. Folia oblongo 

 lanceolaia, acuia. plicata, raullitiervia, basi vaginantia, disticha , scapo breviora, apice 

 recurva. Scapus composito spicaius , vel spica composila, caulem lerminans , com- 

 pressa, erecla, vaginata. Spiculae 1 — 3 pollicares. oblongae, rernotae, densillorae. 

 Flores minuti . conffirti, luteo virides, globri, leviler adnali. Alabastrum trigonum. 

 Sepala palula, laieralia curn basi producta columnne connaia, basi obliqua. acuminaia. 

 Peiala multo angustiora, linearia , subspaihulata , conniventia, apite tantnm recurva. 

 Labellum posiicum , cum pede lorige producto columnae articulatum, trilobum, albuin 

 iobo medio mnjore. plicato, acummaio , subito rellexo, lobis laieralibus faicaiis con- 

 niveniibus ; disco ad medium calloso, a basi ad apicem u*que dense glanduloso. Co- 

 lunina bievis, semiieies, in ovarium resujiinata clinandrio uirinque e.\cavato ad pol- 

 linia recipienda. Antheia.subconica bilotularis sejuo interrupio. Pollinia 4, per paria 

 cohaerenlia, subrotunda , compressa , fiava. Ovorium sulcaiura , glabrum. Habit. in 

 sylvis ad riviim Para. in roinis aiborum. Mart. Apiil. 



Huc : Polijstachija lulcola Hook. a. angustifolia A. Rich. in Ramon de Sagra 

 246. Caule compresso siibancipiti basi incrossato simplici glabro ; loliis 2 — 3 infer- 

 ioribus voginantibus elliptico oblongis oblusis coriaceis, nunc caule dimidio brevi- 

 oribus, nunc subaequalibus ; floribus parvulis luteolis brevissime pediccllaiis , nunc 

 spicam simpiicem, nunc spicos 2—3—4 alternas enorrnaniibu'», fructibus oblongis scx- 

 costatis. 



