40 



A SYNOPSIS OF THE PLANT KINGDOM 



alternating with the petals, free or united with the 

 petals, or with each other; rarely an intrastaminal disk 

 present; ovary inferior, 1-3-cclled; ovules 1-2 in each 

 cell: fruit dry, indehiscent, or capsular. 



Twelve genera and about 50 species occur, all natives 

 of South Africa. The family is related to various fami- 

 lies of the Saxifrage group, as. for instance, the Hama- 

 melidaceas, but is distinct because of its heath-like 

 habit. The flowers are mostly in dense heads. 



The family is of no economic importance. One 

 species of Audouinia (A. capitata) is said to be some- 

 times in cultivation as Diosma capitata. 



100. Hamamelidaceae (from the genus Hamamdis, 

 an ancient Greek name applied to some tree). WITCH- 

 HAZEL FAMILY. Fig. 27. Trees or shrubs: leaves simple, 

 alternate: flowers unisexual or bisexual, hypogynous, 

 perigynous or epigynous; sepals 45; petals 4-5, or 0; 

 stamens 4-5, rarely more; sub-ovarian disk rare; ovary 

 2-celled; ovules 1 or several in each cell: fruit a woody, 

 2-valved capsule, with a separating inner layer of dif- 

 ferent texture; seeds often winged. 



Twenty genera and 50 species are known, widely 

 distributed in subtropical or warm temperate regions 

 of both hemispheres. It is an ancient family more 

 abundant in former ages, related to the Saxifragacese, 

 and by some considered related to the Cornacese or 

 Araliacese. Many fossil species are known. The peculiar 

 fruit is distinctive. 



In some genera, as in Hamamelis, the seeds are 

 forcibly expelled when the fruit opens, often to a dis- 

 tance of 10 feet or more, much as wet apple seeds may 

 be shot from between the thumb and finger. 



The family is of little economic importance. Extract 

 of the bark of Hamamelis is used as a liniment 

 (witch-hazel). The twigs are supposed to have super- 

 normal properties, especially in the detection of water 

 in the earth. They are frequently used in rural districts 

 in the attempt to detect underground springs. Liquid- 

 ambar Styraciflua (sweet gum), of the southern 

 United States, yields a balsam. The oriental balsam, 

 Styrax, is obtained from the eastern L. orientalis. This 

 was formerly used in medicine. 



Perhaps half the genera are in cultivation, all for 

 ornamental purposes. Of these, Fothergilla, Corylopsis 

 Hamamelis, and Liquidambar are the best known. 

 Most of the species are hardy. 



101 . Platanaceae (from the genus Platanus, the ancient 

 name of the tree, signifying broad). PLANE-TREE FAM- 

 ILY. Fig. 28. Trees with alternate, broad, palmately 

 veined leaves: flowers in dense heads, monoecious, regu- 

 lar, perigynous; sepals usually 3-8, separate, thick, often 

 with bracts at the base; petals of the same number, 

 glabrous; stamens of like number alternating with the 

 petals; connective peltate at the top; extra staminodia 

 often present; carpels several, distinct, 1-seeded: 

 fruit a caryopsis, angled from pressure, and truncate 

 at top, surrounded by long hairs at the base; seed 

 orthotropous. 



A single genus and about 6 species are distributed in 

 southern Europe, southern Asia, and in North America. 

 The family is related to the Saxifragacese and Hama- 

 melidaceae. The polypetalous perigynous flower, 

 with as many stamens as petals, the separate carpels, 

 and especially the peculiar inflorescence and leaf, are 

 distinctive. Fossil species are known. 



The wood of Platanus is similar to maple and of 

 value, but the most important use is for ornament. Two 

 species of Platanus (Plane-Tree, Buttonwood, Button 

 Ball, Oriental Plane, Sycamore) are in cultivation in 

 America. 



102. Rosaces (from the genus Rosa, the ancient name 

 of the rose). ROSE FAMILY. Fig. 28. Herbs, shrubs, or 

 trees, often thorny, sometimes climbing: leaves alter- 

 nate, rarely opposite: flowers bisexual, rarely unisexual, 

 usually regular, perigynous; calyx of 4-5 imbricated 

 or valvate sepals; corolla of as many imbricated petals, 



or 0; stamens 5 to many, in whorls of 5, borne on the 

 cup of the receptacle at some dist ance from the carpels ; 

 cup lined with a glandular disk; carpels 1 to many, 

 separate and superior or united and inferior; ovaries 

 1 to several-ovuled; styles as many as the carpels: fruit 

 a follicle, achene, drupe, pome, or hip; seeds usually 

 exalbuminous. 



There are about 90 genera and 1,500 species, widely 

 distributed in all parts of the world, most abundant, 

 perhaps, in the temperate regions. The largest genera 

 are Rubus, 180-200 species; Potentilla, 200 species; 

 and Rosa, 100 species. The family is related to the 

 Saxifragaceae and the Leguminosse, also to the Caly- 

 canthacese. The perigynous flower with cup lined by 

 the glandular disk, the numerous cyclic stamens, and 



10 



28. PLATANACE<E: 1. Platanus, a, flower; b, floral diagram. 

 ROSACES: 2. Fragaria, a, flower; 6, fruit. 3. Geum, fruit. 4. 

 Rosa, a, floral diagram; 6, fruit. 5. Spiraea, fruit. 6. Prunus, a, 

 flower; b, fruit. 7. Pyrus, a, flower; 6, fruit. LEOUMINOS.E: 8. 

 Pisum, a, flower; 6, flower, petals removed; c, fruit. 9. Des- 

 modium, fruit. 10. Cassia, flower. H. Acacia, flower. 



the separate, usually cyclic, carpels, are distinctive. 

 The Ranunculacese is similar, but acyclic and hy- 

 pogynous. 



The family is divided into 6 very distinct sub- 

 families, some of which, by certain authors, are con- 

 sidered of family rank, as follows: I. Fruit folh'cular, 

 e.g., Spiraea, Physocarpus. Aruncus, Sorbaria, and 

 so on. II. Ovary compound, inferior: fruit fleshy, e. g., 

 Pyrus, Cratajgus, Cotoneaster, Cydonia, Amelanchier, 

 Mespilus, and the like. III. Fruit of achenes or 

 separate drupelets, e.g., Rubus, Fragaria, Potentilla, 

 Geum, Cercocarpus, Ulmaria, Alchemilla, Agrimonia, 

 Sanguisorba, and Rosa. IV. Carpels connate, and 

 adnate to the hollow, but dry, receptacle, e.g., Neurada 

 and Grielum. V. Carpel 1, superior: fruit a drupe: 

 style terminal, e.g., Prunus. VI. Same as the last, but 



