In the article published in the December number, allusion was made incidentally to the facility with which Caladiums can be successfully crossed. I now present some additional facts on the subject in connection with a class of plants known to gardeners by the generic name of Diffenbachia, but which are also classed by some botanists as a species of Caladium.

I was fortunate in bringing these two classes of plants into bloom at the same time; therefore you will see there was every reason for believing the result would terminate successfully. I used pollen of Caladiums bicolor, poecile, Houlletii, Neu-manii and six other kinds, on flowers of Dieffen-bachias, picta, Bauseia and Baraquiniana.

One would naturally suppose that if these plants are closely allied species of the same genus, the fact of hybridizing them would be a simple matter, coincident with the skill of the operator and the means of performance. But I find that Caladium pollen has not the least effect on the flowers of Dieffenbachia; that, after having experimented for two seasons on at least two dozen flowers, I could not detect the faintest trace of fertility.

The experiment is another of the series mentioned above. It extended over the same period of time, was carried on simultaneously, and under the same conditions. With the same pollen I successfully crossed, reciprocally, the Caladiums without a single failure; but in attempting to cross the Dieffenbachias with Caladium pollen the result has ended in total failure. On the same plants where this failure occurred I successfully crossed, reciprocally, the Dieffenbachias. But to this subject I shall return in a future number, as I have collected a mass of facts which I cannot utilize at present.

One puzzling incident in connection with this matter I may mention here, as affording a strong contrast to the effect, or rather the non-effect, of the Caladium pollen. I dusted one of the flowers of Dieffenbachia picta with pollen taken from Anthurium crystallinum, which happened to come in bloom at the time. The effect of this was curious; in less than three hours the parts of the flower so dusted turned black, and in the course of three or four days shrivelled and dried up. Was this a sign of incipient fertilization? The flowers of Dieffenbachia usually remain fresh and plump for two or three weeks after being prepared for hybridizing.