DEYEUXIA 
357 
Deherainia Dene. Myrsinaceae (i). i sp. Mex., D. smaragrfina Dene, 
with large green flrs. (coloured by chlorophyll). 
Delima Linn. = Tetracera Linn. 
DelpMnium Tourn. ex Linn. Ranunculaceae (2). 150 sp. N. Temp. 
D. Ajacis L. (larkspur) in Brit. Several sp. are cult, for their flrs. 
Firs, zygomorphic in racemes ; the posterior sepal is drawn out into 
a spur containing the spurs of the two posterior petals, in which the 
honey is secreted. [Cf. this mode of protection with that in Aconitum, 
which is far more frequently robbed by humble-bees.] The flr. is 
protandrous with movement of the sta., and is fertilised by humble- 
bees. The open flr. projects horizontally, but subsequently the stalk 
bends upwards and the follicles stand erect so that the seeds can only 
escape if they are shaken, e.g. by strong wind. 
Dendrobium Sw. Orchidaceae (21). 360 sp. trop. As., Japan, Austr., 
Polynes. Epiphytes. Many are favourites in cultivation. For floral 
mechanism see Darwin’s Orchids , p. 138. 
Dendrocalamus Nees. Gramineae (xm). 10 sp. Indo-mal., China. 
D. giganleus Munro is the giant bamboo, the largest known bamboo 
(cf. Bambusa). It grows with great rapidity (see Lock in Ann . 
Perad., II. 1904, p. 211), even as much as 46 cm. a day (cf. also 
Smith in Ann . Perad. , III. 303). 
Dendrochilum Blume. Orchidaceae (22). 3 sp. Indo-mal. 
Demistaedtia Bernh. Polypodiaceae. 60 sp. trop., S. Am., Austr. 
Dentaria (Tourn.) Linn. = Cardamine Linn. 
Derris Lour. [Deguelia Aubl.). Leguminosae (in. 8). 40 sp. trop. 
Deschampsia Beauv. Gramineae (ix). 20 sp. temp, and frigid. D. 
caespitosa Beauv. (Aira) and D . flexuosa Trin. are common in Brit, 
(hair grass). They are of tufted growth and are rough fodder grasses. 
Desfontainia Ruiz et Pav. Loganiaceae. 1 sp. Andes, D. spinosa R. 
e< P., a pretty holly-like shrub. Its position in the order is doubtful. 
The ovary has 5 loculi. 
Desmanthus Willd. Leguminosae (1. 3). 9 sp. sub-trop. N. Am., 1 
Madag. 
Desmodium Desv. Leguminosae (ill. 7). 150 sp. trop. and sub-trop. 
The most interesting sp. is D . gyrans DC. the telegraph plant (the 
name dates from the days of semaphore telegraphy). During the 
day, provided the temperature be not below 72 0 F. the two small 
lateral leaflets of each leaf move steadily round in elliptical orbits. 
The meaning of this phenomenon is unknown. See Darwin’s Move - 
7 nents of Plants . At night the leaves sleep, drooping downwards. 
Several sp. are useful as fodder plants, and are cultivated like clover. 
Desmoncus Mart. Palmae (iv. 7). 20 sp. trop. Am. Climbing palms 
with reedy stems, and hooks like those of Calamus. 
Deutzia Thunb. Saxifragaceae (ill). 10 sp. N. temp. Ovary imerior 
3 — 4-loc. The fruit splits septicidally into its cpls. which open each 
at its apex. The seed is provided with a winged testa, very light. 
Deyeuxia Clar. = Calamagrostis Adans. 
