OUYIRANDRA 



OXALIS 



1181 



gascar, according to the Botanical Magazine, the plant 

 grows in running water. Some cultivators think that 

 the water must be changed every day, but this is not 

 necessary. If confervas appear, introduce a few tad- 

 poles and snails; these will devour the green scum, and 



1600. Lace-leaf plant Ouvirandra fenestralis. 



help to keep the plant in good health by furnishing 

 oxygen. (See Aquarium.) The plant should be potted, 

 and plunged not more than 18 inches below the sur- 

 face of the water. For potting soil use a rich compost, 

 such as is recommended for Nymphaeas. The water 

 should be kept clean and sweet, and a temperature of 

 65 to 75 provided. Avoid direct sunlight. 



In Madagascar the streams often dry up, and the 

 tubers carry the plant over the dry season. In imitation 

 of nature some cultivators take the tubers out of the 

 soil, and leave them on a shelf in a hothouse during 

 the month of February. It is doubtful whether this is 

 necessary. Potting should be done while the plant is 

 in active growth, not dormant. Prop, by division. 



fenestralis, Poir. (Aponogeton fenestrale, Hook.). 

 Fig. 1600. The fls. are small, and consist of 6 stamens, 

 3 pistils and 2 white petal-like bodies. The fls. are 

 numerous, and borne in 2 spikes, each about 2 in. long, 

 which are united at the base, and borne on the top of a 

 scape a foot or so long. A.F. 7:67. A.G. 15:169. B.M. 

 4894. G.M. 38:830. Gn. 30, pp. 344, 345. Mn. 6, p. 231. 

 F.S. 11:1107. I.H. 8:300. 



O. Bernieriana, Decne., differs in having smaller open spaces 

 in the Ivs., and pinkish 4-parted spikes. 



WM. THICKER and W. M. 



OXALIS (sharp ; referring to the usual acidity of 

 the foliage). Geraniacece, sometimes treated as a fam- 

 ily, Oxalidacece. Over 200 species, mostly of South 

 Africa and tropical and subtropical America. A few 

 are weeds or woodland plants through the northern 

 countries of both hemispheres. Mostly bulbous or 

 tuberous herbs, with clover-like Ivs., cultivated in bor- 

 ders and rockeries or especially as hanging-basket or 

 window plants for their flowers; a 

 few used in salads, and several of 

 the South American species grown 

 for their edible roots or tubers. 

 The fls. usually close at night and 

 in cloudy weather, and the leaves 

 "sleep" at night (Fig. 16011. 



O. Acetosella produces, in addi- 

 tion to the showy flowers, others, 

 concealed by the leaves, which are 

 fertilized in the bud, like those of 

 our native blue violets. The bul- 

 bous and tuberous species com- 

 monly consist of three otherwise 

 similar forms, in the flowers of 

 which the styles are respectively 

 longer than, intermediate between, 

 <xnd shorter than the two sets of 



stamens; but the native O. violacea produces only the 

 first and last of these three forms of flowers, which are 

 designated as long-styled, mid-styled and short-styled. 

 Several species, often treated as belonging to a separate 

 genus, Biophytum, possess pinnate sensitive Ivs. 



Prop, by division of the compound bulbs 

 or separation of the young bulbs produced 

 at the ends of underground roots by some 

 species, or division of the clumps of those 

 which are tuberous, the fibrous - rooted 

 caulescent species prop, by cuttings or 

 division. Nearly all may be grown from 

 seed, but this process is slower, and some 

 rarely seed in cultivation. 



Planted in rich, well-drained sandy loam 

 in spring, they bloom continuously through 

 the season, and are lifted for winter bloom- 

 ing ; sometimes dried off in spring, and 

 started into growth in autumn for indoor 

 baskets, etc. The caulescent species are 

 kept in continuous growth like Pelargo- 

 niums, usually in the temperate house. 



The classical works on Oxalis are Jac- 

 quin's "Oxalis, Monographia, iconibus 

 illustrata" (1794), with exquisite plates; 

 and Zuccarini's "Monographic der Ameri- 

 kanischen Oxalis- Arten," and "Nachtrag 

 zu der Monographie der Amerikanischen 

 Oxalis-Arten " ( 1825-1831 ) . The 69 Chilean 

 species are reviewed by Karl Reiche in 

 Engler's Bot. Jahrb. 18:259-306 (1894). 

 WM. TRELEASE. 



None of the cultivated kinds are hardy, at least in 

 the North. The bulbous or tuberous kinds grown in 

 greenhouses make handsome pot-plants for autumn and 

 winter decoration. They are also favorite house plants, 

 and one frequently sees them displayed as hanging 

 plants. They are easily grown, clean, healthy, and con- 

 tinue a long time in bloom. The roots are started in 

 August or September, and commence growth quickly. 

 Good rich soil is recommended. The crowns should be 

 kept near the surface, and deep pots used, as the plants 

 are liable to lift themselves out. Abundance of water 

 will be required during the growing season, and a little 

 liquid stimulant will help them when in bloom. When 

 going to rest, less water will be required, until finally 

 the pots may be laid on their sides until another season. 



T. D. HATPIELD. 



Acetosella, 6. 

 alba, 8. 

 arborea, 8. 

 atropurpurea, 2. 

 bipunctata, 9. 

 Bowiei, 13. 

 caprina, 14. 

 cernua, 14. 

 corniculata, 2. 

 delieata, 5. 

 Deppei, 11. 

 elongata, 17. 

 esculenta, 11. 

 flava, 14. 

 floribunda, 9. 

 fulgida, 16. 

 grandiflora, 15. 

 hirta, 16. 

 hirtella, 16. 



INDEX. 



Japonica, 7. 

 lasiandra, 12. 

 laxula, 15. 

 lilacina, 8. 

 lutea 14. 

 maritima, 9. 

 Martiana, 9. 

 multiflora, 16. 

 Ortgiesi, 4. 

 ptirpurea, 15. 

 rigidula, 15. 

 rosacea, 16. 

 rosea, 1. 



rubella, 16. 

 rubra, 8. 

 spedosa, 15. 

 suggillata, 15. 

 tetraphylla, 11. 

 tropaeoloides, 2. 

 urbica, 9. 

 Valdiviana, 3. 

 Valdiviensis, 3. 

 variabilis, 15. 

 venusta, 15. 

 versicolor, 17. 

 violacea, 10. 



1601. Leaves of Oxalis tetraphylla, showing day and night positions. 



