MISSOURL BOTANICAL GARDEN BULLETIN 3145 
entrapped insect. In forcing its way out of either of these 
small openings, however, it comes into contact with the 
sticky pollen masses which finally become firmly attached to 
its back. In the next flower visited the same process is 
repeated but in its outward journey the insect rubs its back 
against the stigmatic surface and deposits the pollen masses 
upon it, thus bringing about pollination. 
The pollination of species of Cattleya in the Garden col- 
lection by native bumblebees has been observed several 
times. On one occasion the bee was seen to traverse the 
base of the sepals and petals in close proximity to the nectar 
gland, but it seemed unable, at first, to find the proper avenue 
of entrance. After a time, however, it entered the funnel- 
shaped lip down whose long tube it pushed its way finally 
reaching the nectar gland at the base of the labellum. Its 
next move was interesting. Finding it impossible to turn 
around, it backed out, the lip acting as a spring in keeping 
the back of the bee close to the column. In passing the 
beaked rostellum, the four pollen masses were ejected and 
securely fastened to the bee’s thorax. While the bee was 
captured at this stage and photographed, and subsequently 
kept as a specimen, there can be little doubt that the adher- 
ing pollen would have been deposited upon the stigmatic 
surface of the next flower visited. 
The few cases cited make it apparent that orchid flowers 
not only depend almost exclusively upon insects for their 
pollination, but also that they are so constituted as to insure 
cross-pollination in the great majority of cases. 
Evolution of Hybrids. There are two groups of hybrid 
orchids under cultivation at the present time, the natural 
hybrids, resulting from insect cross-pollination among in- 
digenous species, and garden hybrids, produced by artificial 
cross-pollination. While comparatively few of the former 
have been produced, the number of present day garden 
hybrids is extremely large, especially soi the cypri- 
iums. The development and growing of hybrids is at 
present being carried on extensively by the large commercial 
establishments. 
The first authentic hybrid was raised by Mr. Dominy, of 
England, flowering in October, 1856, and named “Calanthe 
<< Dominii” in honor of the noted hybridist. The parents 
used were Phaius grandifolius (a specimen of which is flower- 
ing in the orchid house at the present time), and a variety 
of Calanthe vestita, the pollen being taken from the latter 
species. For a long period of years following this begin- 
