The reddish-blue Ipomoea, I. rubro-coerulea, is a splendid half-hardy annual climbing plant, belonging to the natural order Convolvulaceae, and is a native of Mexico, where the seeds were collected by Samuel Richardson, in the province of Guanaxuato. Mr. Richardson presented the seeds to J. D. Powles, Esq., of Stamford Hill, England, who first flowered it, and then distributed the plant among cultivators. It is an annual species of rapid, robust growth, attaining a height of some twenty-five or thirty feet by as much in breadth; this of course depending on the soil, situation, and the amount of care and attention bestowed on the plant. The plant has a smooth stem and alternate pale green acuminate leaves. The flowers, which are very freely produced, are of a fine purplish blue and in axillary clusters, each cluster producing from three to five flowers; the time of flowering depending upon the manner in which the plants have been cultivated.

Where a large space is to be covered by a summer climber, I know of nothing much better than this Ipomcea, as it is of rapid growth and stands our hot dry summer weather without sustaining any injury, and moreover, is perfectly free from all insect pests.

In order to cultivate this Ipomcea successfully, the seed should be sown about the middle of March, in a well-drained pot or pan filled with light loamy soil, placed in a warm moist situation as close to the glass as possible, and as soon as the young plants are strong enough to handle they should be transferred into three-inch pots similarly prepared. These young plants should be kept close and moist until well-established, then gradually exposed to the air, and as soon as the weather has become warm and settled - which is about the middle of May - they can be planted outside. Let the place where the plants are to grow be dug to the depth of two feet, and at the same time work in a liberal supply of thoroughly decayed manure. Support should be given the young plants before they commence to run; and during their season of growth they should be looked over occasionally, and the young shoots so trained as to cover the desired space. As soon as hot dry weather sets in, a good mulch of coarse littery manure should be given and a thorough soaking.

Propagation is effected by seeds which are freely produced and ripened from the earliest blooms. The generic name is derived from "ips" bindweed, and "homoios," similar, in allusion to the twining character of the plant; and the specific alludes to the reddish blue color of the inflorescence. Queens, N. Y, January 4th, 1886.