2JO 
BO WLES1A 
Bowlesia Ruiz et Pav. Umbelliferae (2). 12 sp. Am., Canary Is. 
Boykinia Nutt. Saxifragaceae (1). 7 sp. N. Am., Japan. 
Brachycome Cass. Compositae (ill). 50 sp. Austr., N. Z., N. Am., 
Afr. 
Brachypodium Beauv. Gramineae (x). 6 sp. temp, (and trop. Mts.). 
2 in Brit, (false brome grass). Leaf reversed (cf. Alstroemeria). 
Brachysema R. Br. Leguminosae (ill. 2). 14 sp. Austr. 
Bradburya Rafin. = Wistaria Nutt, and Centrosema Benth. 
Brahea Mart. Palmae (1. 2). 2 sp. Mexico, Texas. 
Brainea Hk. Polypodiaceae. 1 sp. Hong-kong and Khasia, B. insig- 
ms Hk., a dwarf tree-fern. The primary veins branch and rejoin 
repeatedly, forming small areas in the leaf ; the veinlets run parallel 
and distinct. 
Brasenia Schreb. Nymphaeaceae (11). r sp. cosmop., except Eur. 
Sta. 12 or more. 
Brassavola R. Br. Orchidaceae (13). 20 sp. trop. Am. 
Brassia R. Br. Orchidaceae (28). 30 sp. trop. Am. 
Brassica (Tourn.) Linn. (incl. Erucastrum Presl. and Sinapis L.). 
Cruciferae (11. 10). 85 sp. Eur.,Medit., As. 7 in Brit. Many forms 
of this genus are cultivated, some for the fir., others for the stem, 
root, leaf, or seed. B. ( S .) nigra Koch is the black mustard, whose 
ground seeds form the familiar condiment; B. (S.) alba Boiss. 
is the white mustard, used when young in salads &c. ; B. sinapis 
Vis. (S. arvensis L.) is the charlock, one of the most abundant 
weeds of cultivation (in summer our corn-fields are yellow with it). 
B. oleracea L. is the cabbage, with the various races derived from 
it, such as cauliflower and brocoli (fleshy infh), kale, brussels- 
sprouts (a form in which miniature cabbages are produced in all the 
leaf-axils on the main stem), kohl-rabi (a thickened stem, or corm, 
showing leaf scars on its surface), &c. B. ca?npestris L. is the turnip, 
a biennial with thickened root, and a variety of it — B. Napus L. — is 
the rape, used in salads and in the preparation of rape- or colza-oil, 
expressed from the seeds. [See De Candolle’s Orig. of Cultiv. Pits .] 
It is of interest to notice here the great variety of morphology in the 
vegetative organs, correlated with the different ways in which storage 
of reserve materials is effected, in the root, stem, leaf, flowerstalk &c. 
The outer coat of the seed has mucilaginous cell- walls which 
swell when wetted and help to fasten the seed to its place of germi- 
nation (cf. Linum). 
Bravoa Lex. Amaryllidaceae (11). 3 sp. Mexico. Rhizome with 
tuberous roots. Fir. zygomorphic by bending. 
Braya Stemb. et Hoppe. Cruciferae (iv. 18). 8 sp. Mts. of Eur., As. 
Brevoortia Wood. Liliaceae (iv). 1 sp. Calif. 
Breweria R. Br. Convolvulaceae (1. 2). 27 sp. trop. 
Brexia Noronha. Saxifragaceae (v). 1 sp. Madag., Seychelles. 
Brickellia Ell. Compositae (11). 60 sp. trop. and sub-trop. Am. 
