122 BOTANY. 



both well-known plants, the former a climber, conspicuous for its showy 

 crimson flowers, the latter a tree with large heart-shaped leaves. 



Jacaranda tomentosa, Mexico {pi. 63, jig. 9). 



Bignonia leucoxylon, Antilles {pi. 63, fig. 10) ; a, the calyx ; h, portion 

 of the corolla tube laid open ; c, pistil ; d, side of the stigma. 



Order 96. Gentianace^, the Gentian Family. Calyx gamosepalous, 

 usually five-divided, sometimes four-, six-, eight-, or ten-divided, persistent. 

 Corolla gamopetalous, hypogynous, usually regular and marcescent ; limb 

 sometimes fringed, divided into as many lobes as the calyx ; aestivation 

 plaited or imbricate-twisted. Stamens inserted upon the corolla, alternate 

 with its segments, and equal to them in number, some of them occasionally 

 abortive. Ovary composed of two carpels, unilocular, or partially bilocular; 

 ovules 00, anatropal ; style one, continuous ; stigmas, one or two. Fruit, 

 capsular or baccate, one-celled, usually bivalvular, with septicidal, or rarely 

 loculicidal dehiscence. Seeds 00, small ; embryo straight, minute, in the 

 axis of soft, fleshy albumen ; radicle next the hilum. Herbs, seldom shrubs, 

 with opposite, rarely alternate, entire or divided, exstipulate leaves, which 

 are often three- to five-ribbed. The plants of the order are distributed 

 generally over the globe, inhabiting both cold and warm regions. They 

 are rare in arctic and antarctic islands. They exhibit great varieties of 

 colors, and many are highly prized for their beauty. 



Suh-order 1. Gentiunece. Lobes of the corolla, twisted to the right in 

 the bud, with the folds at the sinuses, when present, plaited. Leaves almost 

 always opposite or whorled, entire, those of the stem sessile. Tj-ibe 1. 

 Chironiece. Anthers without connective, with the cells opening by a slit, 

 abbreviated into a pore. Examples : Chironia, Lapithea, &c. Tribe 2. 

 Chlorece. A connective. Style distinct, caducous. Examples : Sabbatia, 

 Erythraea, &c. Tribe 3. LisianthecB. A connective. Style persistent, 

 distinct from the double or simple stigmata. Tropical plants, almost 

 exclusively American. Examples : Pagoea, Prepusa, &cc. Tribe 4. 

 Swertiecs. A connective. Stigmata sessile or confluent with the persistent 

 style. Plants inhabiting northern latitudes or the summits of mountains. 

 Examples : Gentiana, Bartonia, Halenia, Frasera. 



Sub-order 2. Meny ant hide cb. Lobes of the corolla valvate in the bud, 

 with the edges turned inwards. Stem-leaves alternate, petioled. Seed 

 coat hard or bony. Plants growing in wet places. Examples : Menyanthes, 

 Limnanthemum. 



Sub-order 3. Obolariece. Lobes of the corolla imbricated in the bud. 

 Leaves opposite, sessile. Ovules covering the whole inner surface of the 

 ovary. Example : Obolaria. 



Lindley assigns 60 genera and about 450 species to the order 

 Gentianaceae. Most of the genera indicated above have North American 

 representatives. 



Gentiana pneumonanthe, common gentian, Europe {pi. 63, fig. 11): 

 a, calyx ; b, corolla displayed ; c, capsule ; d, a seed magnified ; e, 

 seed. 



Order 97. LocANiACEiE. Calyx, four- or five-leaved, with aestivation 

 122 



