136 MALAXE.E. Chap. V. 



other, and afford the only entrance ; but the presence 

 of these two minute windows (fig. 20) shows how neces- 

 sary it is that insects should visit the flower in this 

 case as in that of most other Orchids. How insects 

 perform the act of fertilisation I have failed to under- 

 stand. At the bottom of the roomy and dark chamber 

 formed by the closed sepals, the minute column stands, 

 and in front of it is the furrowed labellum, with a 

 highly flexible hinge, and on each side the two upper 

 petals ; a little tube being thus formed. When there- 

 p. 20 ^^^'® ^ minute insect enters, or 



^^.^^^^ which is less probable, a larger in- 

 /^'^ '> ^^'f^^ sect inserts its proboscis through 

 '''< ^ 'tj either window, it has to find by 

 the sense of touch the inner tube 

 i/ in order to reach the nectary at 



y the base of the flower. Within 



^^^/A — ^ the little tube, formed by the 



Masdevallia fenes- column, labellum, and lateral 

 TRATA. petals, a broad and hinged rostel- 



The window on the near side inm proi'ects at rifi^ht auHes, 



IS shown darkly shaded. i • i -n i , t 



which can easily be upturned. 



Its under surface is viscid, and 

 this viscid matter soon sets hard and dry. The minute 

 caudicles of the pollinia, projecting out of the anther- 

 case, rest on the base of the upper membranous surface 

 of the rostellum. The stigmatic cavity when mature 

 is not very deep. After cutting away the sepals I 

 vainly endeavoured, by pushing a bristle into the 

 tubular flower, to remove the pollinia, but by the aid 

 of a bent needle, this was effected without much 

 difficulty. The whole structure of the flower seems 

 as if intended to prevent the flower from being easily 

 fertilised ; and this proves that we do not understand 

 its structure. Some small insect had entered one of 



