A SYNOPSIS OF THE PLANT KINGDOM 



23 



This is an important family of more than 400 genera 

 and between 6,000 and 10,000 species. Orchids are very 

 widely distributed, except in the arctics, but are most 

 numerous in the tropics. Those of temperate regions 

 are mainly terrestrial; those in the tropics commonly 

 epiphytic. The large genera are Epidendrum, 500 spe- 

 cies; Habenaria, Dendrobium, Bulbophyllum, and Un- 

 cidium, 200^600 species each; Masdevallia, Odonto- 

 glossum, and Maxillaria, each 100 or more species. 



From the standpoint of the intricate and very special 

 mechanisms evolved in order to insure cross-pollination, 

 the orchids are the most wonderful of our insect- 

 pollinated plants. For a detailed account see Darwin's 

 "Fertilization of Orchids," or Kernerand Oliver's "Natu- 

 ral History of Plants." In general, the insect visiting the 

 showy flower for the honey comes in contact with the 

 sticky gland above the stigma, thereby pulling it out, 

 along with the attached pollen masses. While the insect 

 is going to another flower, the pollen masses dry and 

 bend down until they are in position to strike the viscid 

 stigma, which tears away and retains some of the pollen. 

 The method of pollination in Cypripedium is fundamen- 

 tally different. Some orchids (e.g., Catasetum) possess a 

 sensitive explosive mechanism that forcibly ejects the 

 pollen mass, often to the distance of 2 or 3 feet. The 

 minute seeds of the orchids are well adapted to be 

 disseminated by the wind and find lodgment in the 

 crevices of the bark of trees and on other supports. 

 Orchids are divided into large groups as follows: 

 Group I. Diandrse. The two lateral stamens of the 

 inner whorl fertile, the dorsal of the outer whorl 

 staminodial or fruitful, the others absent. Cypripe- 

 dium, Selenipedium, Paphiopedilum, and others. 



Group II. Monandrae. The dorsal stamen of the 

 outer whorl fruitful, all the others wanting. By far 

 the majority of the species belong here. Subgroup I. 

 Pollinia connected by caudieles with a gland at base 

 of anther near stigma. Subgroup 2. Pollen without 

 caudieles or with these attached to a gland at apex of 

 anther. 



The family is very distinct and easily distinguished. 

 Its only near relatives are the Burmanniaceae. The 

 peculiar structure of the stamens and pistil, together 

 with the minute exalbuminous seeds are distinctive. 



The Orchidaccae is perhaps the most important 

 family from the standpoint of ornamental gardening. 

 To grow these singular, fantastic, showy, and often 

 sweet-scented flowers has in recent years become almost 

 a craze. It is estimated that, whereas Linmeus knew 

 but a dozen exotic orchids, at the present day more 

 than 2,500 are known to English horticulturists. 

 Plants in the family useful for other purposes are few. 

 The most important is vanilla, derived from the capsule 

 of Vanilla planifolia of Mexico, and now widely culti- 

 vated in the tropics. Faham (Angrxcum fragrans of 

 Bourbon) has a fragrant, bitter-almond-like taste; the 

 leaves are used for indigestion and tuberculosis, and are 

 known as Bourbon tea. Salcp is derived from the 

 roots of various terrestrial orchids of the Mediterra- 

 nean region. The roots of helleborine (Epipaclis lali- 

 folia) are used for rheumatism. The root of Spiranthes 

 diurelica of Chile is renowned as a diuretic. The flow- 

 ers of Habenaria conopsea are used for dysentery. Spi- 

 ranthes aulumnalis and Habenaria bifolia are said to 

 be aphrodisiac. The roots of Cypripedium paniflorum 

 var. pubescens are frequently used in America as a 

 substitute for valerian. 



CLASS II. DICOTYLEDONE.E 

 Sub-class 1. Archichlamydese (Choripelalse and Apetalx) 



Order 22. VERTICILLALES 



47. Casuarinaceae (from the genus Casuarina, de- 

 rived from the resemblance of the branches to the 

 feathers of the bird cassowary). CASUARINA FAMILY. 



Fig. 14. Shrubs, or much-branched trees, with the habit 

 of the horse-tail (Equisetum) or Ephedra: branches 

 whorled, jointed, striate: leaves replaced by striate, 

 many-toothed sheaths: flowers monoecious ordioscious, 

 the staminate in spikes, the pistillate in heads ; perianth 

 of the staminate flower of 2, rarely 1, bract-like parts; 

 stamen 1; perianth of the pistillate flower 0; ovary 

 1-celled, rarely 2-celled, 2-4-ovuled; stigmas 2: fruit 



14. CASUARINACEJ:: 1. Casuarina, a, portion of male inflores- 



HLOHANTHACE.E: 4. Chloranthus, a, flower, vertical section; 



dry, often samaroid, inclosed by the woody valve-like 

 bracts; seeds 2, or 3-4, orthotropous, ascending. 



A single genus containing about 20 species occurs in 

 Australia and the neighboring islands, extending to 

 Madagascar and to southeast Asia. The family is very 

 distinct and its relationships are in doubt. It is placed 

 here in the system because of the simple flowers. The 

 peculiar habit, reduced staminate flowers, and peculiar 

 fruit are characteristic. 



The wood of Casuarina equisetifolia is very hard, and 

 called ironwood. It is used in ship-building, and by the 

 Indians for war-clubs; the powdered bark is used to 

 dress wounds, or for diarrhea. A brown dye is obtained 

 from the same plant. 



A few species of Casuarina (Beefwood, She Oak) are 

 cultivated in the South for timber and ornament. 



Order 23. PIPEEALES 



48. Saururaceae (from the genus Saururus, meaning 

 lizard's tail, in allusion to the long slender spike). 

 Liz ARD'S-T AIL FAMILY. Fig. 14. Herbs : leaves alternate, 

 large and broad: flowers bisexual, regular, in a long, 

 dense spike; perianth 0; stamens 6 or fewer, hypo- 

 gynous or united with the pistil; carpels 3-4, separate, 

 or united in to a 3-4-celled ovary; ovules 2 to several, 

 parietal; stigmas as many as the carpels: fruit of 

 follicles, or a lobed berry. 



Three genera and about 4 species are found in tem- 

 perate or subtropical Asia and North America. The 

 family is related to the Piperacea, with which it is 

 frequently united. From that family it differs in 

 having several carpels in each flower and several 

 parietal ovules for each carpel. 



Saururus cernuus (lizard's tail), a native herb, is 

 in the trade as a garden plant for wet soil. 



49. Piperacese (from the genus Piper, an ancient 

 name of pepper). PEPPER FAMILY. Fig. 14. Herbs, 

 shrubs, or rarely trees: leaves alternate, rarely opposite 

 or whorled: flowers in dense spikes, bisexual, or uni- 

 sexual, regular; perianth 0; stamens 1-10; ovary 



