OENOTHERA. 



194 



OFFSETS. 



they do not flower well if they are kept 

 too hot. 



Nymprea. — Nymphacece. — The 

 Water Lily. One species of this 

 beautiful plant grows wild in England, 

 but there are others, some blue and 



some pink, from Egypt, which must 

 be grown in the aquarium of a hot- 

 house to induce them to flower in 

 England. They should be grown in 

 a rich loamy soil, and kept in the 

 warmest part of the stove. 



Ocynum. — Labiates. — Basil. 

 Some of the East India perennial 

 species are ornamental, and worth 

 cultivating in the stove, where they 

 should be grown in sandy loam. 



Odontoglossum. — OrchidacecB. — 

 A splendid genus of Mexican epi- 

 phytes, requiring the usual treatment 

 of similar plants. See Orchideous 

 Epiphytes. 



(Enothe^a. — Onagraceee. — The 

 Evening Primrose. Perennial, bien- 

 nial, and annual plants, with large 

 flowers. The yellow and white 

 flowering kinds, which are the true 

 evening primroses, are now the only 

 ones left in the genus, the pur- 

 ple-flowered ones having been re- 

 moved to the genus Godetia. The 

 evening primroses have the peculi- 

 arity of only opening their flowers in 

 an evening, or when the sun is over- 

 cast ; as, contrary to the habits of 

 most other flowers, they seem unable 

 to bear much light. They are all of 

 the easiest culture, and will grow in 

 any common garden soil, without any 

 other care than occasionally taking up 

 and replanting the perennial kinds, 

 and sowing the annual and biennial 

 ones every year in March or April. 

 Of the biennial kinds, CE. noctuma 

 and CE. villosa, both natives of the 

 Cape of Good Hope, are rather ten- 

 der ; and of the perennials, CE. rosea, 

 (E. ccespitosa, and CE. anisoloba, 

 require a slight protection during 

 winter. CE. acaulis, which is a na- 

 tive of Chili, though a common bor- 

 der flower, should have a flower-pot 



or hand-glass turned over it in severe 

 frosts ; CE. ccespitosa, and CE. aniso- 

 loba, both splendid plants, should 

 also be protected during winter, par- 

 ticularly from heavy rains, as they are 

 very apt to damp off if they are ex- 

 posed to too much moisture. Pax ton 

 recommends removing the damp soil 

 from the roots of these plants when 

 growing in the open ground in Octo- 

 ber, and after replacing it with dry 

 soil, covering the plant with dry saw- 

 dust, and setting a flower-pot over it, 

 the hole in the bottom having been 

 first stopped to keep out the snow and 

 rain. In this state it should remain 

 till March, when the sawdust should 

 be removed, and the plant covered 

 with a hand-glass till it can bear ex- 

 posure to the cold. Both kinds should 

 be grown in a mixture of peat and 

 loam ; and both are propagated by 

 dividing the root into pieces about an 

 inch and a half long in autumn, and 

 planting them. 



Offsets are a natural means by 

 which plants propagate themselves. 

 In bulbs, the offsets are small bulbs 

 which form by the side of the princi- 

 pal one, from which they should be 

 broken off when the bulbs are taken 

 up and replanted. In shrubs and peren- 

 nial plants, the offsets either spring 

 from the collar of the old plant or 

 from an underground stem ; and in 

 both cases, as they are provided with 

 roots of their own, though they draw a 

 part of their support from the main 

 stem, they only require dividing and 

 replanting to form new plants. 



