(Jbaf. VII. CrCNOCHES VENTKICOSUM. 221 



fig. 34 ; in which the pedicel of the poUinium has not 

 as yet become separate from the rostelluni, but the 

 future line of separation is shown by a line (dotted 

 in the figure) of hyaline tissue. The filament of the 

 anther (/, fig. 34) has not as yet grown to its full 

 length. When fully developed it bears two little leaf- 

 like appendages which lie on the anther. Lastly, 

 on the sides of the stigma there are two slight 

 protuberances (fig. 33), which apparently represent 

 the antennae of Catasetum, but have not the same 

 function. 



Neither the labellum nor the protuberances on the 

 sides of the stigma are at all sensitive ; but when on 

 three occasions I momentarily touched the filament, 

 between the little leaf-like appendages, the poUinium 

 was ejected in the same manner and through the 

 same mechanism as in Mormodes ; but it was thrown 

 only to the distance of about an inch. If the filament 

 had been touched by an object which had not been 

 quickly removed, or if by an insect, the viscid disc 

 would certainly have adhered to it. Mr. Veitch informs 

 me that he has often touched the end of the column, 

 and the poUinium has adhered to his finger. When 

 the poUinium is ejected, the pedicel forms a hoop, with 

 the exterior surface of the curtain of the disc resting 

 on and covering the anther. In about fifteen minutes 

 the pedicel straightens itself, and the anther-case 

 drops off ; and now the poUinium is in a right position 

 for , fertilising another flower. As soon as the viscid 

 matter on the imder surface of the disc is exposed to 

 the air it quickly changes colour and sets hard. It 

 then adheres with surprising force to any object. 

 From these various £9,cts and from the analogy of the 

 other Catasetidae, we may conclude that insects visit 

 the flowers for the sake of gnawing the labellum ; 



