COL VILLEA 
3 21 
forms with variegated and coloured leaves, are in cultivation. C. 
elongatus Trimen is a peculiar sp. found only on the top of one moun- 
tain in Ceylon, and must have arisen by mutation (Ann. Perad. iv. i). 
Colletia Comm. Rhamnaceae. 13 sp. S. Am. The habit is very 
peculiar ; in each axil are two serial buds, of which the upper gives 
rise to a triangular thorn, while the lower forms firs, or a branch of 
unlimited growth. 
Collinsia Nutt. Scrophulariaceae (11. 6). 17 sp. N. Am., often culti- 
vated as border-plants. The flr. exhibits a close resemblance, both 
in shape and mechanism, to that of many Leguminosae. 
Collomia Nutt. Polemoniaceae. 18 sp. N. W. Am. and Chili. The 
seed coat has an outer covering of cells with mucilaginous walls which 
swell rapidly when wetted, thus anchoring the seed to a suitable 
place for germination (cf. Brassica, Linum, &c.). 
Colobanthus Bartl. Caryophyllaceae (11. 1). 10 sp. S. Am., Austr., 
N. Z. Petals o. Sta. in one whorl. 
Colocasia Schott. Araceae (vi). 6 sp. E. Ind. Tuberous herbs or 
small shrubs. Monoecious. Sta. in synandria. C. antiquorum 
Schott, the taro, eddoes, coco, or scratch-coco, is largely cultivated 
in the tropics for its rhizomes, which when boiled lose their poisonous 
nature and form a valuable food stuff. 
Colpodium Trin. Gramineae (x). 12 sp. Medit., Centr. As., Arctic. 
Colquhounia Wall. Labiatae (vi. 4). 4 sp. Indo-mal. 
Colubrina Rich, ex Brongn. Rhamnaceae. 15 sp. trop., subtrop. 
Columellia Ruiz et Pav. Columelliaceae. 2 sp. Peru, Ecuador. Shrubs 
with evergreen opp. exstip. leaves. Firs, in cymes, $ , nearly regular. 
K5, C (5), A 2. Sta. short and thick with irregular broad connective 
and 1 twisted pollen sac. No disc. G (2), imperfectly 2-loc. Ovules 
00 , anatropous. Style short and thick with broad 2 — 4-lobed stigma. 
Capsule, enclosed in calyx. Endosperm. 
Columelliaceae. Dicotyledons (Sympet. Tubiflorae). Only genus Co- 
lumellia (q.v.). This order represents an old and now isolated type 
(p. 120) and has been placed in many positions. It is placed in 
Personales by Benth. -Hooker. [Cf. Van Tieghem, Ann. Sc. Nat. 8. 
xviii. 155.] 
Columnea Linn. Gesneraceae (1). 70 sp. trop. Am. Several are 
climbers and epiphytes. Anisophylly is frequent (p. 47). 
Columniferae (Warming). The 12th cohort of Choripetalae (p. 138). 
Colutea (Tourn.) Linn. Leguminosae (ill. 6). 10 sp. S. Eur. to 
Himal. C. arbor escens (L. bladder-senna) is frequently cultivated. 
Its leaves have similar properties to those of senna (Cassia) and 
are used to adulterate the latter. The pods are inflated and burst on 
being squeezed. They may break off and blow about and thus scatter 
the seeds, or may catch the wind while still on the plant, and jerk 
out the seeds as they sway. 
Colvillea Boj. ex Hook. Leguminosae (11. 7). 1 sp. Madag. 
W. 
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