G, M. Taomson,—0On the Fertilization of some New Zealand Orchids. 419 
lie very closely ensconced in the anther case. For fertilization by insects, 
however, the parts are very simply fitted. The rostellum with the attached 
caudicle projects to a small point, and is viscid on the edge and under-surface. 
An insect visiting the flower would insert its head or proboscis into the 
small square aperture between the labellum and the column, and in with- 
drawing would inevitably touch the viscid surface. The slightest touch 
brings away the pollinia, usually all four, but sometimes only two. Were 
they to be withdrawn just as they lie on the summit of the column, they 
would hardly be in the position to strike the stigmatic surface of another 
flower; but in being withdrawn, the cap of the anther pulls them slightly 
downwards and depresses the caudicle considerably. I repeatedly imitated 
the action with the point of a pencil or needle, and found in every case that 
the pollinia came away readily, and were depressed considerably below a 
right-angle to the surface to which they adhered. In this position they 
were easily placed on the stigma of a second flower. I carefully examined 
91 flowers, and found that the pollinia had been removed from the anthers 
in 41 cases, and remained intact in 50; this too in bright, warm weather. 
Of course the plants were not in their native habitat, which might account 
partly for lack of the usual bush-frequenting insects. Those spikes pro- 
minently placed on the plant usually had the pollinia of their flowers more 
or less removed, while those which were buried among the leaves had not 
as a rule been visited, 
Tribe Maraáxr. 
(2.) Dendrobium cunninghamii, 
This beautiful orchid has its flowers evidently fitted for cross-fertiliza- 
tion. The upper sepal is lanceolate in form, and is the smallest in the 
whorl. The lateral sepals are broad at the base, and adnate to the 
produced base of the column. The lateral petals are linear oblong. 
The labellum is widely expanded above the middle, with two small lateral 
lobes, and bears on its face five elevated ridges or plates, It is attached 
to the base of the column by a short and very elastic claw. The column 
stands in the flower exactly like the letter J, being produced forward at the 
base, and terminated by a large green glandular swelling. en the 
flower is open, a small drop of nectar is always found at the base of 
this swelling. The erect portion or limb of the column is rather long. 
The anther is terminal, and encloses four narrow and flattish pollen 
masses, attached in pairs to a strap-shaped caudicle. The stigmatic 
surface is placed slightly below it, and is nearly square. When in the 
bud, the lower surface is hollowed into a deep pit, and on its summit, 
standing directly in front of the bases of the pollinia, is the rostellum, 
which at this early stage is membranous, As the flower opens, the cells 
