frost of four or five degrees did not injure the foliage, we again examined the plants, and found an abundant crop of tubers just below the surface of the soil, and varying in size from that of peas to pigeons' eggs. The plants were left till the haulms had been destroyed by cold, after which the tubers were gathered. On cooking some of the larger ones by boiling for half an hour, we found them still rather hard, and with a flavor of potatoes, almost concealed under a strong earthy taste, quite disagreeable and soap-like. Considering how short a time these tubers had had to grow in it is not improbable that their hardness and disagreeable taste were owing to their being unripe; no doubt young, green potatoes (these Ullucus tubers were partly green) would be quite as nauseous as these were. [Illustration: MELLOCO TUBERS.] We are told that the Ullucus is extensively cultivated in Peru and Bolivia, in the elevated regions where the common potato also thrives, and with which the Ullucus is equally popular as a tuber-yielding plant. In the _Gardeners' Chronicle_ for 1848, p. 862, Mr. J.B. Pentland stated that the Ullucus "is planted in July or August, the seed employed being generally the smaller tubers, unfit for food, and is gathered in during the last week of April. These two periods of the year are the spring and autumn in the southern hemisphere. The mode of cultivation is in drills, into which the root is dropped, with a little manure. The climate, even during the summer season, is severe, scarcely a night passing over without the streams being frozen over, the sky being in general cloudless at all periods of the year except during the rainy season (December to March). Mean temperature about 49°." This information seems to support the view formed of this plant from its behavior at Kew last year, namely, that the tubers are formed on the approach of cold weather, and that, so long as the weather is warm and bright, leaves only are developed. Plants grown in houses where the temperature has not been allowed to fall below 50° in winter did not form any tubers, although they were in good health. We found no tubers on the plants grown out of doors till some time after the return of cold, wet weather. It seems likely that this plant does not develop tubers unless its existence is threatened by cold; at all events, such a conclusion seems reasonable from the above statements.