FLOWERING PLANTS AND FERNS OF ARIZONA 561 



in 4's, the petals spreading at anthesis; ovary 2-celled; berries 1- to 

 4-seeded. 



1. Cissus trifoliata L., Syst. Nat. ed. 10, 2: 897. 1759. 



Santa Cruz and Pima Counties, 3,000 to 5,000 feet, not common, 

 usually among rocks clambering over bushes, July and August. 

 Southern Arizona, Mexico, and widely distributed in tropical America. 



The plant has a rank, disagreeable odor suggesting that of jimson- 

 weed {Datura). The tubers are reputed poisonous, and contact with 

 the plant causes dermatitis in susceptible persons. 



73. TILIACEAE. Linden family 



1. CORCHORUS 



Plants herbaceous (in Arizona) ; leaves alternate, simple, with ser- 

 rate blades; flowers perfect, regular, solitary or few on short peduncles 

 opposite the leaves; petals 4 or 5, yellow; stamens numerous; ovary 

 superior. 2- to 5-celled; capsule long and slender, 2-valved. 



Two Old World species furnish the important fiber jute. 



1. Corchorus hirtus L., Sp. PL ed. 2, 747. 1762. 



Apparently the only record for Arizona is a collection from " sandy 

 plains near the Mexican boundary"' (Pringle in 1884), August. 

 Southern Arizona, Mexico, and widely distributed in tropical America. 



Pringle's specimens are small, with stems only about 6 cm. long. 

 They probably belong to var. glabellus Gray. 



74. MALVACEAE. Mallow family 



Plants herbaceous or shrubby, with more or less mucilaginous 

 juice, usually pubescent with stellate or forked hairs; leaves simple, 

 alternate, petroled, stipulate; flowers regular, perfect; calyx often 

 subtended by a calyxlike involucel; petals 5, hypogynous, convolute 

 in the bud, asymmetric, more or less united at base to the stamina! 

 column; stamens numerous, monadelphous; anthers 1-celled, reniform; 

 pollen grains large, spiny; carpels 3 or more, 1-celled; style usually 

 several-branched; fruit a loculicidal capsule, or, in most of the genera, 

 the mature carpels separating from one another and from the recep- 

 tacle; seeds often pubescent. 



This family is notable as the one to which the cotton plants (Gossy- 

 pium spp.) belong. Cotton is an important crop in Arizona and a 

 peculiar form (Gossypium kopi Lewton), distantly related to upland 

 cotton (G. hirsutum L.), was cultivated by the Hopi Indians from 

 prehistoric until very recent times. There is, however, no record 

 of its growing wild anywhere in the State. The garden vegetable 

 okra (Hibiscus escvlentus) also belongs to the Malvaceae. Many 

 plants of this family have showy flowers, and numerous species of 

 Hibiscus, Malm, etc., are cultivated as ornamentals. The marsh- 

 mallow (Althaea officinalis L.), a European plant with thick mucilag- 

 inous roots, is used in making the well-known confection, also medic- 

 inally. 



