756 



TREES OF NORTH AMERICA 



flower, calyx minute, 5-lobed, persistent under the fruit; corolla polypetalous, petals 5, 

 linear-oblong, erect, ultimately spreading above the middle, deciduous; ovary free, sessile, 

 1-celled or more or less spuriously 5-celled; style or abbreviated; stigmas 5, linear, radiat- 

 ing, dilated and subpalmately lobed at apex; ovules indefinite, inserted in two rows on the 

 placenta, anatropous, long-stalked; micropyle superior; raphe ventral; hermaphrodite 

 flower, corolla gamopetalous, tubular-campanulate, the lobes erect and spreading or sub- 

 reflexed; stamens 10, in 2 ranks, or 5; ovary obo void-oblong, longer than the tube of the 

 corolla, more or less spuriously 5-celled below. Fruit slightly 5-lobed,' 1-celled or more or 

 less completely 5-celled, filled with soft pulp, many-seeded, that produced from the herma- 

 phrodite flower long-stalked, pendulous, usually unsymmetric, gibbous, and smaller than 

 that from the pistillate flower. Seeds ovoid, inclosed in membranaceous silvery white sac- 

 like arils, occasionally germinating within the fruit; seed-coat crustaceous, closely invest- 

 ing the membranaceous inner coat, the outer coat becoming thick, rugose, succulent, and 

 ultimately dry and leathery; embryo in the axis of fleshy albumen; cotyledons ovate, 

 foliaceous, compressed, longer than the terete radicle turned toward the minute pale 

 subbasilar hilum. 



Carica with aljput twenty species is distributed from southern Florida through the West 

 Indies to southern Brazil and Argentina, and from southern Mexico to Chili. One species 

 grows probably indigenously in Florida. The milky juice of Carica contains papain, which 

 has the power of digesting albuminous substances, and the leaves are often used in tropical 

 countries to make meat tender. 



The generic name is formed from the Carib name of one of the species. 



1. Carica Papaya L. Pawpaw. 



Leaves ovate or orbicular, deeply parted into 5-7 lobes divided more or less deeply into 

 acute lateral lobes, these secondary divisions entire or rarely lobed, the lowest lobes form- 



Fig. 681 



ing a deep basal sinus, thin, flaccid, yellow-green, 15'-24' in diameter, with broad flat 

 yellow or orange-colored primary veins radiating from the end of the petiole through the 

 lobes, and small secondary veins extending to the point of the lateral lobes and connected 

 by conspicuous reticulate veinlets; petioles stout, yellow, hollow, enlarged and cordate at 

 base, sometimes becoming 3-4 in length before the leaves fall. Flowers often begin- 

 ning to appear on plants only 3 or 4 high and a few months old, produced continuously 

 throughout the year, the staminate in clusters on slender spreading or pendulous peduncles 

 4'-12' long, the pistillate in 1-3-flowered short-stalked cymes; staminate flowers fragrant, 

 filled with nectar, their corolla f '-1|' long, with a slender tube and acute lobes; anthers 



