G. M. Tromson. 
On the Fertilization of some New Zealand Orchids. 495 
of the anther, and is slightly viscid. The pollen-masses, four in number, 
are very incoherent. From their inconspicuous colour, the fact of their being 
very frequently closed, and the extreme incoherence of their pollen, I am 
inclined to think that the flowers of this plant are always self-fertilized. I 
examined 89 flowers, and found that the pollinia were present in all of 
them, but in the more advanced some of the pollen was scattered over the 
stigmas, and the ovaries appeared well-developed. 
Tribe Nrorrez. 
(9.) Thelymitra longifolia. 
The fertilization of this orchid is treated of in Fitzgerald’s “ Australian 
Orchids,” and quoted by Darwin. All the parts of the perianth, including 
the labellum, are similar in colour and shape. The column is nearly erect, 
and slightly hooded at the apex. On its front margin, and a little below 
the apex, a projection occurs on each side, bearing a tuft of exquisitely 
beautiful feathery hairs. These are the auricles or staminodia which 
represent two out of the three stamens of the inner whorl, the third being 
the only stamen fully developed. In this flower they form a very con- 
spicuous feature, but I do not know their function, if any. Placed quite in 
at the back and near the base of the column, are the two persistent anther 
lobes. In very young buds these contain the pollinia, but as they approach 
maturity they become attached to the back of the stigma, which stands 
forward a slight distance from the column. The pollinia are composed of 
four sheets or plates of white, powdery, very incoherent pollen. The 
rostellum is hardly viscid at all, nor would this be of any use to the plant, 
as itis seldom, if ever, visited by insects. The flowers are seldom found 
open, and as a rule are probably self-fertilized. I presume that the pollen 
grains emit their tubes to the upper surface of the stigma, but I never 
succeeded in detecting this, 
(10.) Prasophyllum colensoi. 
The flowers are small and greenish-brown in colour. The base of the 
ovary is sheathed by a short truncate bract; the very short pedicel is not 
twisted, so that, as in Thelymitra, the labellum appears in its normal position 
above the flower. All the parts of the perianth are similar in form and 
colour. The column is very short and erect, with the anther placed at tho 
back. At each side rises a small two-lobed appendage, representing 2 
staminodium or imperfect stamen about half the height of the column. 
The stigmatic surface is broadly triangular, and is protected in front by the 
labellum, and latterly by the staminodia. The pollen grains are usually 
found adhering to the back of the stigma, some on its upper edge. When 
examined under the microscope, some of these were found to havo 
emitted a mass of short tubes. The pollinia are two in number, and the 
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