CONVOLVULACE^E. 
251 
Porana contains three species : the first, racemosa, is a green¬ 
house, climbing annual, which, in warm situations, will produce 
its pretty clusters of white flowers in the open air; the other 
two, paniculata and volubilis, are stove, climbing annuals^ having 
also white flowers, borne in clusters. They are pretty, but less 
effective than some others which have been mentioned. Loam 
and leaf-mould suits them, and the syringe must be frequently 
in use while they are growing. 
Quamoclit. A genus of thirteen species, mostly tender, climb¬ 
ing annuals, of limited habit and numerous small, gaily-coloured 
flowers. Q. phoenicea is a neat little hardy annual, with ascend¬ 
ing stems of some three feet in height, bearing small scarlet 
flowers, and is the only species which will bear exposure. Q. vul¬ 
garis, better known as Ipomcea quamoclit, is a familiar summer 
occupant of the greenhouse, and may serve as an illustration of 
the culture of the entire genus. The seeds should be sown on 
light, rich earth in March, and plunged in brisk heat. The 
young plants require potting separately as soon as the seed- 
leaves are fully developed, and afterwards to be shifted as they 
grow till they stand in eight-inch pots, and, in the course of the 
progress, supports of some description must be introduced, to 
sustain the flexile stems. The pretty orange-scarlet flowers begin 
to appear in July, and continue through the summer. There is 
also a white-flowering variety of this species. Perhaps the most 
deserving of this genus are, coccinea, scarlet; serotina, orange ; 
grandiflora, scarlet; longijlora, white ; and triloba, purple. 
Rhodorhiza. The only species, R. scoparia , or, as it is com¬ 
monly known, Canary Rosewood, is a greenhouse, subscandent 
plant, with twiggy branches, rising about three feet high, clothed 
with linear leaves, and bearing white blossoms in twos and threes. 
It grows best in peat and loam, and is increased by cuttings or 
seed. 
Rivea is an interesting genus, containg four species, all stove, 
climbing perennials, with large, handsome, white flowers. R. 
bona-nox is the most familiar, its name of Good-night being allu¬ 
sive to the opening and closing of its flowers. The other species 
are, hypocrateriformis, with large, wide-mouthed flowers—it 
is the Lettsomia uniflora of Roxburgh ; ornata, a handsome 
species, also included in the genus Lettsomia by Roxburgh; and 
