MA8DEVALLIA. 55 



that " when an insect ah'ghts on it, it suddenly shuts up against 

 the column and encloses its prey, as it were, in a box/^ We extract 

 from the Gardeners^ Chronicle of 25th June, 1887, the following 

 account of the curious mechanism by which this is effected : — 



" When a flower first opens, the tails of the sepals curve back 

 and the labellum is seen Avith its bearded tip folded just beneath the 

 arch of the petals as if held there. Presently, however, the triangular 

 blade falls down and hangs like the lip of an Oncidium ; this, 

 on being first observed, was surmised to be owing to sensitiveness, 

 and on testing it this surmise was found to be correct. The seat of 

 irritability is only in the yellow ridge on the lip, and on touching 

 this gently with a hair, the lip is at once raised, at first slowly and 

 then closed suddenly, as it Avere, with a click. In about twenty 

 minutes it descends again, and on being again touched it closes just 

 as quickly as before. A winged aphis placed on the labellum was 

 carried up and held firmly, and the same happened Avhen a house-fly, 

 was tried. Attempts to force the lip doAvn again after it closed 

 showed that the sensitiveness Avas of precisely the same nature as that 

 of Dionma Muscipula (Venus' Fly-trap), and it could not be made to 

 remain doAvn unless held. An insect alighting on the labellum Avould 

 certainly touch the ridge, and Avould be lifted up and enclosed in the 

 "box" formed Avhen the lip is closed. The excessiA^e hairiness of the 

 scapes and ovaries, altogether exceptional among the cultivated Masde- 

 vallias, is no doubt .intended to preA'ent craAvling insects from gaining 

 access to the floAvers." 



This curious plant was one of the discoveries of Shuttleworth, 

 in New Granada, near San Domingo, on the central Cordillera, in 

 the province of Tolima, while collecting orchids in that country for 

 Mr. Bull, of Chelsea, The sensitiveness of the labellum was first 

 observed by Mr. Bean, the foreman of the orchid department at 

 the Royal Gardens, Kew ; and to the Royal Gardens also we are 

 indebted for the materials for description. 



M. nycterina. 



Leaves linear-oblanceolate, 6 — 8 inches long, scapes pendulous or 

 decumbent, shorter than the leaves, Avarty, deep purple, Avith a small 

 pale acute bract at the base of the ovary, one-floAvered. FloAvers 

 patent, triangular in outline ; uj^per sepal triangular, connate with the 

 lateral two at the base, Avhich are ovate-triangular, and connate to below 

 the middle, all keeled behind and contracted into slender, purple-red 

 tails 3 inches long, the inner surface light yelloAV spotted Avith red, 

 purple, and studded Avitli short Avhite hispid hairs ; petals oblong- 



