58 



connection between the pollinia and the rostellum. The 

 column has grown in height, carrying the anther with it ; but 

 the anther-case still guards the pollen in such a way that when 

 it falls it can only do so in one direction, viz., down upon the 

 stigma. The closed segments of the perianth no doubt help 

 to further facilitate and ensure this result. In the bud the 

 labellar petal is in close apposition with the front of the column 

 and extends slightly beyond lateral appendages. 



At a still later stage of development (fig. 3) the column 

 has increased in height and width, the dehiscing margins of 

 the pollen-cases have retracted far back, and the friable pollen 

 is seen to be massed upon these and upon the interlocular 

 septum, just above the rostellum and the stigma. Some of 

 it has already fallen upon the latter. The falling of the pollen 

 is brought about by the ordinary action of gravity, by the 

 shaking of the flower, or by the movement involved by the 

 separation of the cases from the pollinia and the upward move- 

 ment of the anther itself. 



Very often after most of the pollen has fallen a consider- 

 able quantity still adheres to the shrivelled cases for a time, 

 but eventually reaches the stigmatic surface. Any pollen fail- 

 ing to fall directly upon this surface will, nevertheless, be 

 caught in the cup-like depression (fig. 4) formed by the wings 

 of the column at the base of the stigma, and will in this way 

 be available for purposes of fertilization. 



The function of the pencillate appendages is not very clear. 

 Possibly they are intended to guard against misplace nent of 

 the pollen in an upward direction, such as might occur from 

 violent shaking of the flower in windy v/eather. 



The whole process of dehiscence of the anther a.nd sub- 

 sequent pollination may be observed at leisure by stripping the 

 perianth from a suitable bud and watching the column on a 

 warm day. 



Thelymitra fuscolutea, Br. PI. ix.A. 



The flower of this orchid is yellow with dark-brown spots, 

 and is sufficiently conspicuous to suggest cross-pollination. 

 Such, however, does not appear to be the case. The flowers 

 open in hot weather, and nearly all become fertilized. On 

 twenty-two plants chosen at random I counted 104 flowers. 

 Out of those ninety-nine were fruiting. The plant blooms in 

 November and December, the hot weather apparently being 

 advantageous in several ways, especially in drying and pul- 

 verizing the pollen. The anterior or labellar petal is more 

 differentiated in this species than in most Thelymitras, and 

 is always shorter and narrower than the lateral petals. 



