156 BOTANY. 



Momordica balsaminea, Balsam apple (East Indies) {pi. 71, fig. 12) ; a, 

 branch with flowers and fruit ; b, male flower ; c, do. without corolla ; d, 

 female flower ; e, cross-section of the young fruit ; f, the fruit burst open ; 

 g, a seed ; h, do. without the testa ; /, cross-section of do. 



Bryonia alba (Europe) (pL l\,fig. 13) ; A, branch with male, B, do. with 

 female flowers ; C, root ; a, male flower ; b, do. expanded ; c—d, stamens ; 

 e, female flower ; /, do. with the corolla cut away ; g, stigma ; h, fruit ; i, 

 cross-section of do. ; k, seed. 



Order 142. Loasace.i3, the Chili Nettle Family. Calyx four- or five- 

 parted, persistent, spreading in aestivation. Petals five, cucullate, epigynous, 

 alternate with the segments of the calyx, sometimes with an inner row of 

 five, which are either similar to the outer or dissimilar ; aestivation inflexed, 

 valvate, or twisted. Stamens » in several rows, distinct, or polyadelphous, 

 each parcel being opposite the outer petals ; filaments subulate, unequal, the 

 outer ones often sterile. Ovary inferior, one-celled, with parietal plaoentas ; 

 ovules anatropal ; styles combined into one ; stigma one or several. Fruit 

 capsular, or succulent, one-celled. Seeds without an arillus ; embryo 

 straight, in the axis of fleshy albumen ; cotyledons small, flat ; embryo 

 pointing to the hilum. Herbaceous plants, hispid with stinging hairs, 

 having opposite or alternate exstipulate leaves, and axillary one-flowered 

 peduncles. They are American plants, chiefly distinguished for their 

 stinging qualities, and hence the name of Chili Nettle. There are fifteen 

 genera enumerated by Lindley, including seventy species. Examples : 

 Loasa, *Mentzelia, Gronovia, *Cevallia. In North America there are of 

 this order, JMentzelia with twelve, and Cevallia with one species. 



Order 143. Haloragace^, the Mares-tail Family. Calyx with a minute 

 limb, which is either three- or four-divided or entire ; it is sometimes 

 reduced to a mere rim. Petals epigynous or 0. Stamens epigynous, equal 

 in number to the petals, or twice as many, rarely fewer ; when the petals 

 are wanting, stamens often one or two. Ovary cohering with the tube of 

 the calyx, with one or more cells, sometimes tetragonal or compressed 

 Style 0, what is frequently called the styles being the papulose stifjmas, 

 which are equal in number to the cells ; ovules pendulous, anatropal. 

 Fruit dry, indehiscent, membranous or bony, with one or more cells. Seed 

 solitary or in pairs, pendulous ; albumen fleshy or thin ; embryo straight, or 

 slightly curved, in the axis of the albumen ; cotyledons minute ; radicle 

 superior, long. Herbs, or undershrubs, often aquatic, with large air 

 cavities, having alternate, opposite, or whorled leaves, and axillary, sessile 

 flowers, which are occasionally unisexual. They are found in ditches and 

 lakes in various parts of the world. They have no properties of 

 importance. There are eight known genera, and about seventy species. 

 Examples : *Hippuris, Myriophyllum, Haloragis, Callitriche, *Proserpinaca. 

 North American species twelve. 



Order 144. ONACRACEiE, the Evening Primrose Family. Calyx tubular, 



the limb having usually four, sometimes two, three, or six divisions, which 



cohere in various ways ; aestivation valvate. Petals usually equal in 



number to the calycine segments, regular (rarely irregular), inserted into 



156 



