116 ENGLISH BOTANY. 
ORDER V.—CRUCIFER A. 
Annual or perennial herbs, or rarely under-shrubs, with 
watery often somewhat acrid juice. Leaves alternate (very rarely 
opposite), entire, or dissected; the radical leaves often runcinate ; 
the stem leaves auriculate at the base, and destitute of stipules. 
Flowers usually white, yellow, or purple, in racemes, which are 
commonly terminal. In many species the inflorescence is corym- 
bose until after flowering, when it lengthens into a raceme. 
Pedicels usually not springing from bracts. Flowers perfect, 
regular, or radiant. Sepals 4, deciduous or caducous, imbricated 
in 2 whorls or rarely valvate, the outer or lateral pair often 
bulging at the base. Petals 4, spreading in the form of a cross, 
and alternating with the sepals, convolute or imbricate in estiva- 
tion, generally equal, narrowed into a claw at the base; the limb 
entire, emarginate, or bifid. Receptacle with 2 to 4 (rarely 6) 
glands. Stamens 6, hypogynous, generally free, the two lateral 
ones with shorter filaments than the other four, which are equal, 
and in pairs opposite the inner pair of sepals. Anthers 2-celled, 
dehiscent longitudinally. Ovary free, of 2 carpels situated right 
and left of the axis; placeatas parietal; ovary most frequently 
divided longitudinally into two cells by a partition (replum) 
uniting the placentas. Styles united, often undistinguishable. 
Stigma simple or bilobed. Ovules several or solitary in each cell, 
generally suspended, campylotropous or amphitropous, with the 
raphe ventral. Fruit a long pod (siliqua) or short pouch (silicula), 
2-celled, or rarely 1-celled by the dissepiment (replum) between 
the placentas being incomplete, generally opening by two valves, 
rarely indehiscent, or lomentaceous. Seeds ex-albuminous ; embryo 
bent or curled, rarely coiled; cotyledons plane with the radicle 
applied to their edges (aceumbent), or plane with the radicle 
applied to the back of one of them (incumbent), or folded longi- 
tudinally (conduplicate) with the radicle lying at the back of one of 
them, rarely twice folded or spirally coiled. 
Exceptions in the British Genera.—The petals are occasionally 
absent by abortion in Cardamine impatiens, Cochlearia Armoracia, 
and Lepidium ruderale; and the stamens are only 2 in Lepidium 
ruderale, and only 4 in Cardamine hirsuta; and in Senebiera didyma 
the stamens are seldom more than 4, and sometimes only 2. 
i 
