G. M. Tuomson.—On the Fertilization of some New Zealand Orchids. 423 
the stigma, thus ensuring fertilization. I found this to be the case in 
several hundred flowers which I examined. The position of the labellum 
on the underside of this flower is caused by the usual twisting of the pedicel 
or ovary, which is so common in many orchids. But in young buds the 
posterior sepal is lowest and placed on the side farthest from the axis of the 
spike ; and it is during the gradual maturing of the flower that the twisting 
takes place, so that, by the time it opens, the labellum and posterior sepal 
have changed places. 
This species, as might be expected from its facilities for reproduction, is 
one of the commonest plants of the class. 
(5.) Caladenia bifolia. 
Chiloglottis traversii, Müeller. 
This is a most abundant orchid in upland districts at an elevation of 
1500 to 8000 feet. The flower is solitary on an erect scape, three to four 
inches in height. The upper sepal is obtuse, somewhat arched forward, and 
slightly keeled. The lateral sepals are placed under the labellum, and 
extend forward almost horizontally. The labellum is broad; on each side 
of the expanded portion is a yellow-coloured patch bearing two or three 
brownish spots, while extending from the middle to the base are two rows 
of yellow glands. The column is long and erect, slightly winged above, 
and bearing a terminal anther which encloses four pollinia. The stigma is 
rounded and slightly hollowed out, and is placed in close contiguity to the 
anther. The arrangement of the parts is so simple that an insect alighting 
on the labellum and advancing its head into the base of the flower could 
hardly fail to remove the pollinia; nor could one entering with pollen on 
its head fail to leave these on the stigma, for in withdrawing pollinia 
from a flower they are always slightly depressed by the cap of the anther. 
The pollen of this plant is very incoherent, and the lower surface of the 
stigma projects a little, so that I am inclined to think self-fertilization takes 
place in flowers which have not been visited by insects. The majority of 
the flowers appear to set good capsules, and flowers which I fertilized 
artificially, produced good full seed-vessels. I examined one sunny day 
twenty-two flowers growing in the open; of these only three had both 
pollinia removed; in one the pollinia were removed from one anther lobe; 
in five others the pollen masses appeared more or less disturbed; while in 
the remaining thirteen the anthers were untouched. 
(6.) Pterostylis banksii. 
The fertilization of the flowers of this genus has been so well described 
by Mr. Cheeseman, in the Trans. N.Z. Inst., Vol. V., p. 852, that I cannot 
well add to it, but my observations on them more than ever induce me to 
consider that there has been an unusual scarcity of iusect life during the 
