CEROPEGIA 
299 
Firs, monoecious, axillary, sessile, with sepaloid perianth. In 
the c?, P about (12), hypogynous; A 12 — 16 on convex recept., with 
oval non-cutinised pollen. In the ? , P (9 — 10), hypogynous; G 1, 
the midrib anterior; ovule 1, orthotropous, pendulous. Achene 
crowned by the persistent style, which in C . demersum is hooked. 
Seed albuminous. The fir. is water-pollinated ; the anthers break off 
and float up through the water (each has a sort of float at top of 
theca) ; the pollen is of the same specific gravity as water (cf. Zostera) 
and thus drifts about till it comes in contact with a stigma. 
Ceratopteris Brong. Polypodiaceae. Only sp. C. thalictroides Brong., 
an aquatic fern (floating or rooted in shallow water) found through- 
out the Tropics. The succulent fronds are eaten as a vegetable in the 
Indian Archipelago. 
Ceratostema Juss. Ericaceae (ill. 8). 20 sp. S. Am. Included in 
Thibaudia H. B. et K. in Nat . PJl . 
Ceratostigma Bunge. Plumbaginaceae. 4. sp. Abyss., Himal., China. 
The total infl. is racemose, the partials dichasial. 
Ceratozamia Brongn. Cycadaceae. 6 sp. Mexico. 
Cerbera Linn, (inch Tanghinia Thou.). Apocynaceae (1. 3). 6 sp. 
Ind. to New Caled., Madag. 
Cercis Linn. Leguminosae (11. 4). 5 sp. S. Eur., As., N. Am. 
C. Siliquastrum L., the Judas-tree, flowers in the open in Brit. 
(Judas is said to have hanged himself on one.) The firs, appear 
before the leaves, in little bunches on the older twigs, and have a 
very papilionaceous look, the two lower petals enclosing the essential 
organs. Serial buds are formed in the leaf axils. 
Cereus Mill, (inch Cephalocerens Pfeiff., Echinocereus Engelm., Echi- 
nopsis Zucc., Pilocereus Lem.). Cactaceae (1). 220 sp. Am., W. Ind. 
Most are erect cylindrical forms, rarely branched, with ribs or less 
often mammillae (see order). A few of the more interesting sp. may 
be mentioned. C. giganteus Engelm. (Texas) is the largest of the 
cacti ; it grows to 70 ft. high and 2 ft. thick with candelabra-like 
branching (figs, in Treas. of Bot. and other books). C. grandijiorus 
Mill, is the night-flowering cactus, whose magnificent and sweetly- 
scented firs, open in the evening and wither before morning. Other 
sp., e.g. C. triangularis Mill., behave in the same way. These 
sp. are mostly trailing forms with adventitious roots upon the stems. 
C. (P.) senilis Salm-Dyck. is the old-man cactus, so called because 
of the long white hairs with which it is covered. A number of cases 
of close resemblance may be found between sp. of C. and sp. of 
Euphorbia. The fruit of most sp. is edible, and is often made into 
preserves. 
Cerinthe Linn. Boraginaceae (iv. 4). 7 sp. Eur., Medit. 
Ceropegia Linn. Asclepiadaceae (11. 4). 80 sp. Afr., As., Austr. 
Erect or twining herbs or undershrubs, more or less xerophytic. 
Many have tuberous rootstocks, others are leafless and sometimes 
