70 THE ORCHID REVIEW. (FEBRUARY, 1913. 
It has a broad white dorsal sepal, with a green base and some purple 
blotches. It was sent as a form of C. Troilus (a hybrid derived from 
C. nitens and C. insigne), for which C. Romulus is a much earlier name. 
We have received from Messrs. James Veitch & Sons, Langley, two 
forms of an interesting hybrid from Cypripedium Thalia crossed with the 
pollen of C. Fairrieanum ; also a flower of the seed bearer for comparison. 
C. Thalia is partly derived from C. Fairrieanum, and the seedlings show a 
marked return to the character of the latter species. The dorsal sepal is 
copiously blotched, and one formis much darker than the other. The 
seedlings are from the same capsule, and are now flowering for the first 
time. They should develop into fine things when the plants become stronger. 
THE ORCHID EMBRYO-SAC, 
AN important paper on the Orchid Embryo-sac, by Lester W. Sharp, 
appears in the November issue of the Botanical Gazette (liv. pp. 372-385, 
tt. 21-23). During the spring of 1910 the author visited Jamaica, with a 
party of botanists, and took the opportunity of studying the embryo-sac of 
a number of Orchids, and these were supplemented by observations on a 
few other cultivated species. 
Orchids, remarks the author, standing at the end of a great evolutionary 
line, the Monocotyledons, and reaching extreme specialisation in other 
features, may be expected to show instructive deviations from the usual 
type of embryo-sac, and it is through a study of such deviations that a final 
explanation of the origin and nature of the angiosperm embryo-sac will 
probably be reached. 
The species studied were Epidendrum variegatum, E. verrucosum, 
E. cochleatum, E. globosum, Phaius grandifolius, Corallorhiza maculata, 
Broughtonia sanguinea, Bletia Shepherdii, Ccelogyne Massangeana, and 
Pogonia macrophylla. Details showing the course of development of the 
embryo-sac from the megaspore mother cell in the different species are 
given, but are difficult to summarise apart from the series of fifty-five 
figures with which the paper is illustrated. A point of interest brought out 
is the variability within the species, involving a reduction of the number 
of divisions occurring between the megaspore and the egg. When a single 
megaspore produces the 8-nucleolate sac there are three such divisions; 
when a similar sac arises from a daughter cell, two megaspores thus taking 
part in the process, there are two divisions; and when the megaspore 
mother cell gives rise to the sac directly, four megaspores are involved and 
the egg is separated from the megaspore by but one division. It was hoped 
“to discover among these advanced angiosperms a situation parallelling that 
in animals, in which the product of the reduction divisions at once becomes 
the egg. 
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