We did not know that there was any movement in the stamens of the night-blooming cereus, though it has been noticed in the common Opuntia, Portulaca, Purs-slane, and allied plants. The following note from the Gardeners' Chronicle, is in relation to Mr. Castle's recent work on cactaceous plants:

"We should gladly have heard more from the author regarding the movements of the stamens and the process of fertilization, and further proof of his allegation that the pollen and stigmas are mature at the same time, in the majority of the species. If this be really so, and not, as we suspect, merely apparently so, we are at a loss to conceive the use of the glorious colored petals, or the fragrance of the night-flowering cereus. The movements of the stamens in the latter plant are very marked, without any external aid, such as a touch. In olden days it was naturally supposed that this motion of the stamens was a provision to secure the deposit of pollen on the stigma of the same flower, and so possibly it may be, but if so, of what use is the fragrance? So far as we know, no one has recorded the condition of the stamens and stigma in these plants, since the publications of Darwin have shown the vast importance of cross-fertilization".

Echo only answers the question as to the use of fragrance to a cactus. Suppose we say it is to attract night moths to the honey secreted at the base of the tube. It will take a pretty long-tongued moth to get down the tube of some of our cereuses. In latifrons and phyllanthoides, the tube is often nearly a foot long. And then in those very arid places, where these flowers "waste their fragrance on the desert air," there are scentless kinds, which ought to have as much need of fragrance.