_Bidentate_, having two teeth (not twice or doubly dentate). _Biennial_, of two years' continuance; springing from the seed one season, flowering and dying the next, 38. _Bifarious_, two-ranked; arranged in two rows. _Bifid_, two-cleft to about the middle. _Bifoliolate_, a compound leaf of two leaflets, 59. _Bifurcate_, twice forked; or more commonly, forked into two branches. _Bijugate_, bearing two pairs (of leaflets, &c.). _Bilabiate_, two-lipped, as the corolla of Labiatæ. _Bilamellate_, of two plates (_lamellæ_), as the stigma of Mimulus. _Bilobed_, the same as two-lobed. _Bilocellate_, when a cell is divided into two _locelli_. _Bilocular_, two-celled; as most anthers, the pod of Foxglove, &c. _Binary_, in twos. _Binate_, in couples, two together. _Bipartite_, the Latin form of two-parted. _Binodal_, of two nodes. _Binomial_, of two words, as the name of genus and species taken together, 180. _Bipalmate_, twice palmately divided. _Biparous_, bearing two. _Bipinnate_ (leaf), twice pinnate, 58. _Bipinnatifid_, twice pinnatifid, 57. _Bipinnatisect_, twice pinnately divided. _Biplicate_, twice folded together. _Biserial_, or _Biseriate_, occupying two rows, one within the other. _Biserrate_, doubly serrate, as when the teeth of a leaf are themselves serrate. _Bisexual_, having both stamens and pistil. _Biternate_, twice ternate; i. e. principal divisions three, each bearing three leaflets, 59. _Bladdery_, thin and inflated. _Blade_ of a leaf, its expanded portion, 49. _Bloom_, the whitish powder on some fruits, leaves, &c. _Boat-shaped_, concave within and keeled without, in shape like a small boat. _Border_ of corolla, &c., 89. _Brachiate_, with opposite branches at right angles to each other. _Brachy-_, short, as _Brachycarpous_, short-fruited, &c. _Bract_ (_Bractea_), the leaf of an inflorescence. Specially, the bract is the small leaf or scale from the axil of which a flower or its pedicel proceeds, 73. _Bracteate_, furnished with bracts. _Bracteolate_, furnished with bractlets. _Bracteose_, with numerous or conspicuous bracts. _Bractlet_ (_Bracteola_), or _Bracteole_, is a bract seated _on_ the pedicel or flower-stalk, 73. _Branch_, _Branching_, 27. _Breathing-pores_, 144. _Bristles_, stiff, sharp hairs, or any very slender bodies of similar appearance. _Bristly_, beset with bristles. _Bristle-pointed_, 54. _Brunneous_, brown. _Brush-shaped_, see _aspergilliform_. _Bryology_, that part of botany which relates to Mosses. _Bryophyta_, _Bryophytes_, 163. _Bud_, a branch in its earliest or undeveloped state, 27. _Bud-scales_, 63. _Bulb_, a leaf-bud with fleshy scales, usually subterranean, 46. _Bulbils_, diminutive bulbs. _Bulbiferous_, bearing or producing bulbs. _Bulbose_ or _bulbous_, bulb-like in shape, &c. _Bulblets_, small bulbs, borne above ground, 46. _Bulb-scales_, 46. _Bullate_, appearing as if blistered or bladdery (from _bulla_, a bubble).