194 BOTANY. 



single; stigina simple. Fruit capsular, three-, five-, to ten-valved, either 

 one-celled or imperfectly five- to ten-celled, with loculicidal dehiscence. 

 Seeds usually indefinite ; embryo inverted, either spiral or curved, in the 

 midst of mealy albumen ; radicle remote from the hilum. Shrubs or 

 herbaceous plants with entire, opposite or alternate, stipulate or exstipulate 

 leaves. They inhabit chiefly the southern regions of Europe, and the 

 north of Africa. Some of the species are remarkable for the irritability 

 <»f their stamens. Many of them ^aeld a resinous balsamic juice, which 

 imparts viscidity to the branches. The resinous matter called ladanum or 

 labdanum, is yielded by Cistus creticus. Of the seven genera and 185 

 tipecies which are assigned to Cistaceaj, North America has twelve species, 

 and three genera. 



Helianthemum vulgare (Europe) {pi. 6S,ßg.S)\ J, the red flowering 

 variety. 



Order 206. Flacouktiace^, the Arnotto Family. Sepals four to seven, 

 slightly cohering. Petals equal to and alternating with the sepals, or 

 wanting. Stamens hypogynous, equal in number to the petals, or some 

 multiple of them. Ovary roundish, sessile, or slightly stalked ; style either 

 none or filiform ; stigmas several, more or less distinct; ovules attached to 

 parietal placentas, which sometimes branch all over the inner surface of the 

 valves. Fruit one-celled, containing a thin pulp, either fleshy and inde- 

 hiscent, or capsular witlj four or five valves. Seeds numerous, enveloped 

 in a covering formed by the withered pulp ; albumen fleshy, somewhat oily ; 

 embryo axile, straight ; radicle turned towards the hilum ; cotyledons flat, 

 t'oliaceous. Shrubs or small trees, with alternate, simple, usually exstipulate 

 leaves, which are often dotted. The plants are chiefly natives of the 

 warmest parts of the East and West Indies, and of Africa. 



Sah-order \. Flaccmrtianece. Placentas ramifying over the inner surface 

 of the fruit. Tribe \. Flacourtiece. Fruit dehiscent. Example: Flacourtia. 

 Tvihe 2. Erythrospennece. Fruit indehiscent. Example : Erythrospermum. 



Suh-order 2. BixaceoR. Placentas narrow and running in lines along the 

 parietes. Trihe 3. Bixiecp. Fruit dehiscent. Flowers hermaphrodite. 

 Example : Bixa. Tribe 4. Carpotrochecc. Fruit indehiscent. Flowers 

 ot^en unisexual. Example : Carpotroche. 



The entire order embraces thirty-one genera and eighty-five species, none 

 of them North American. The most important is Bixa orellana, the plant 

 yielding arnotto. This is the reddish pulp suri'ounding the seeds, and is 

 used to color cheese, and for various red dyes. 



Bixa orellana, Arnotto tree (South America) {pL 68, ßg. 7) ; «, a 

 flowering branch ; b, anther ; c, pistil ; iZ, ^, capsule in verticle and cross- 

 section ; y, burst capsule. 



Order 207. Resedace^, the Mignonette Family. Calyx many-parted. 

 Petals four to six, unequal, entire, or lacerated, in the latter case consisting 

 of a broad scale-like claw, with a much-divided limb. Stamens ten to 

 twenty-four, hypogynous, attached to a glandular torus; filaments variously 

 united ; anthers bilocular, innate, with longitudinal dehiscence. Ovary 

 sessile, three-lobed, one-celled, multiovular, with three to six parietal 

 194 



