A SYNOPSIS OF THE PLANT KINGDOM 



57 



Water Lemon, May-Pop), some for the beautiful and 

 odd flowers, some, especially in the South, for the fruit. 



153. Caricaceae (from tlie genus Carica, erroneously 

 supposed to be a native of Caria; or from the Latin 

 meaning a kind of dry fig). Pawpaw Family. Fig. 4L 

 Peculiar trees with straight, rarely branched, palm-li]<e 

 trunks, very abundant milliy juice, and a terminal crown 

 of very large, alternate, paknately-lobed, rarely entire, 

 leaves: flowers unisexual, small, nearly regular; sepals 

 5; petals 5, in the staminate flowers connate, in the 

 pistillate nearly separate; stamens about 10, inserted 

 on the corolla; ovary superior, 1- or .5-celled, many- 

 seeded; styles 5: fruit a large melon-like berry. 



This is a small fiunily of 2 genera and 27 species, con- 

 fined to tropical and subtropical America; most abun- 

 dant in the Andes. The Caricaceae is united with the 

 PassifloraceiB by some authors, but is similar only in 



41. Cahicace.e: 1. Carica, one form of flower opened. Loasa- 

 ce.e: 2. Loasa, a, flower; b, floral diagram. 3. Mentzelia, a, 

 flower; b, c, and d, types of foliage hairs. Begoniace^e; 4. Begonia, 

 a, male flower; h, female flower; c, cross-section ovary. Cactace.e; 

 5. PiJoceretas, flower. G. Opuntia, flower 



the fruit. It is also related to the Cucurbitaceae bj' the 

 fruit. The peeuhar habit and abundant milky juice are 

 very distinctive. 



The large melon-like fruits of Carica Papaya are now 

 cultivated and eaten throughout the tropics; those of 

 other species are also eaten. The milky juice of C. 

 Papaya contains a pepsin-like substance which will 

 curdle milk. This substance will separate the fibers of 

 meat, and hence the leaves and fruit are cooked with 

 too fresh tough meat to make it tender. The juice 

 has also been used as a remedy for dyspepsia. 



Carica Papaya (South American pawpaw) is com- 

 monly grown in greenhouses; and it, as well as two 

 other species, are grown in southern Cahfomia and 

 Florida in the open. 



1.54. Loasaceae (from the genus Loasa, the meaning 

 unknown). Loasa Family. Fig. 41. Erect or climbing 

 herbs, rarely shrubby, with very peeuhar and charact er- 

 istic hairs, some hooked, some stinging: leaves oppo- 

 site or alternate, verj' diverse: flowers bisexual, regular, 

 mostly perigynous (i.e., receptacle usually extended 



beyond the ovary); sepals 4-5, imbricated; petals 

 4-5, flat or cucullate; stamens 4—5, alternating with the 

 petals, or more commonly very numerous through 

 doubUng, the outer often converted into staminodia 

 which resemble the petals; ovary usually inferior, and 

 1-celled, with 3 parietal placentse; ovules numerous: 

 fruit a capsule, rarely indehiscent, often spirally con- 

 structed. 



There are 13 genera and about 120 species confined 

 to America from the Great Plains to Chile; most abun- 

 dant in South America. This is a distinct family dis- 

 tantly related to the Passifloracea; and the BegoniaceiB. 

 The very peculiar hairs constitute a good recognition 

 character. On Mentzelia there are three types of hairs: 

 (1) Chinese pagoda-like, broad at the base; (2) tuber- 

 cul ate stem and harpoon-Uke top; (3) smooth stem and 

 harpoon top. The flowers with many staminodia are 

 often large and cactus-like. Very queer, grotesque, com- 

 plex scales are produced in the flowers of certain genera 

 (e. g., Loasa) through the union of several staminodia. 



Mentzelia hispida is a strong purgative, and is used 

 by the Mexicans for syphilis. 



A few genera are in cultivation in North America. Of 

 these, Loasa is hke a nettle, and the sting is very painful, 

 but the flowers are queer and interesting. Mentzelia 

 comprises a number of garden annuals or biennials 

 often with large showy flowers. 



155. Begoniaceae (from the genus Begonia, named in 

 honor of Michael Begon, a French promoter of botany). 

 Begonia Family. Fig. 41. Herbs, rarely shrubby, 

 hairs usually scale-like or branched: leaves alternate, 

 usuaUy oblique: flowers monoecious, regular, epigynous, 

 cjonose, the staminate opening first; perianth of the 

 staminate flowers of 2 valvate sepals and 2 petals, all 

 petaloid; perianth of the pistiUate flowers of 2 to many 

 similar petaloid parts; stamens numerous, separate or 

 nearlj- so; ovary inferior, 2-3-celled, usually sharply 

 angled and winged; ovules numerous; styles 3, more or 

 less branched and bearing very peeuhar crescent- 

 shaped, kidney-shaped, or, more often, spiral, velvety 

 stigmas, rarely straight: fruit a capsule, rarely a berry. 



The Begonia family has 4 genera and about 500 

 species, most of which belong to the genus Begonia. 

 They are widely chstributed throughout the tropics, but 

 perhaps most abundant in South America along the 

 Andes to Mexico, and in the eastern Himalayas south- 

 eastward to the Malay Peninsula. The Begoniacea; 

 constitute a distinct group remotely related to the Cac- 

 tacea;, Loasacese, Passifloracea; and Cucurbitaceie. 



The family is of little economic importance except 

 for ornamental purposes. Many species contain oxalic 

 acid and are eaten as salad, and as a remedy for scurvy-. 

 The roots of some are astringent; others have a purga- 

 tive root, used in certain tropics for sj'phiUs and scrofula. 

 The Begoniaceae is one of the most important orna- 

 mental families. 



Very many species and hybrids of Begonia are grown 

 for greenhouse and bedding purposes, both for the 

 flowers and the foliage. 



Order 43. Opuntiales 



1.56. Cactaceae (from the old I/innaan genus Cactus, 

 a name used by the ancients to denote any spiny plant). 

 Cactus Family. Fig. 41. Fleshy plants with watery or 

 milky juice, a great reduction or complete absence of 

 foliage, and very thick, rather .sparingly branched, rarely 

 unbranched stems, which are cylindrical, globular, 

 fl.attened, or fluted, and often constricted or jointed: 

 leaves alternate, flat and leaf-like in Pereskia, scale-like 

 or absent in other genera, usually bearing bundles of 

 spines in the axils, which are trichomes, and which are 

 of two kinds, long and stout, or minute and needle-like: 

 flowers bisexual, mostly regular, perigynous or epigy- 

 nous; sepals and petals rarely 8-10, usually very many, 

 similar; stamens many, inserted spirally or in groups 



