20 



Bolbophyllum barbigerum (Fig. 3) is remarkably interesting, and 

 has been described by Dr. Lindley as follows : " The lip is oneoi 

 the most extraordinary organs known, even amongst orchidaceous 

 plants. It is a long, narrow, flexuose, sharp-pointed body, closely 

 covered with a yellow felt ; just within its point is a deep purple 

 beard of exceedingly fine hairs ; on the under side, at a little dis- 

 tance from the point of the lip, is another such beard ; and 

 besides these there is, at the end of the lip, a brush, consisting of 

 very long purple threads, so exceedingly delicate that the slightest 

 disturbance of the air sets them in motion, when they wave 

 gently to and fro, like a tuft of threads cut from a spider's web. 

 Some are of the same thickness throughout, others terminate in 

 an oblong club, so that when the hairs are waving in the air (and 

 I do not know that they are ever entirely at rest) a part floats 

 gracefully and slowly, while others are compelled by the weight 

 of the glandular extremities to a more rapid oscillation. Nor is 

 this all. The lip itself is articulated with the column by such a 

 very slight joint that to breathe upon it is sufficient to produce a 

 rocking movement so conspicuous and protracted that one is 

 really tempted to believe that there must be something of ar. 

 animal nature infused into this most unplant-like production." 

 Megaclinium falcatum and M. maximum have curiously rolled- 

 up lips, which oscillate in front of the column, but the movement 

 is more marked in the former of the two species. In the southern 

 genus Pterostylis, several species, such as P. longifolia, have 

 sensitive labellums, which, when touched by an insect, spring up 

 to the column, temporarily imprisoning the visitor, and com- 

 pelling it, in effecting its escape, to carry off the pollinia. These 

 contrivances are all connected with the fertilisation of the flower, 

 and in addition to the colours, fragrances, and various mechanical 

 attractions, an inducement is offered to many insects in certain 

 projections upon the labellum. These, insects, chiefly bees, have 

 been seen to gnaw in some species of Catasetum, Gongora, Cory- 

 anthes, and Oncidium, while no doubt many others offer a 

 similar temptation to various insects. These projections are 

 occasionally very prominent, and, as seen in Zygopetalum 

 maxillare, resemble the jaws of some animals, while in Phalaenopsis 

 grandiflora it has been compared to an anvil. The lip is often 

 hinged to the base of the column, swinging up and down at the 

 slightest touch, as seen in the Masdevallias, some of the Bate- 

 mannias, and others. 



The colouring upon the labellum is frequently disposed in lines 

 DF bands, which seem to serve as a means of directing insects to 

 the column, and the lip is, in the majority of cases, so placed that 

 it is a most convenient landing-stage for any that are disposed to 

 visit the flowers, and whatever its form or appearance the attrac- 

 tion of these creatures is evidently its chief function. To aid in 



