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142 This contrivance is not common to all the species of the genus; for in neither D. bigibbum nor D. formosum was the filament of the anther elastic, nor was the middle line of the labellum thickened. In D. tortile the filament is elastic; but as I examined only a single flower, and before I had made out the structure of D. chrysanthum, I cannot say how it acts.

Mr. Anderson states that on one occasion the flowers of his Dendrobium cretaceum did not expand, and yet they produced capsules, one of which he sent me. Almost all the numerous seeds in this capsule contained embryos, thus differing greatly from the cases presently to be given of the self-fertilised seeds from the non-expanded flowers of a Cattleya. Mr. Anderson remarks that Dendrobiums are the sole representatives of the Malaxeæ which, as far as he has seen, spontaneously form capsules. He likewise states that in the immense group of the Vandeæ, hereafter to be described, none of the species under his care, with the exception of some belonging to the sub-division of the Brassidæ and of Sarcanthus parishii, has ever spontaneously produced a capsule.

EPIDENDREÆ.

The Epidendreæ and Malaxeæ are characterised by the pollen-grains cohering into large waxy masses. In the latter of these groups the pollinia are said not to be furnished with caudicles, but this is not universally the case, for they exist in Masdevallia fenestrata and some other species in an efficient condition, although unattached and of minute size. In the Epidendreæ, on the other hand, free or unattached caudicles are always present. For my purpose these