PAPAW 453 



CARICACE-E, OR PAPAW FAMILY 



A family composed of two genera of latex-containing trees, 

 growing in tropical America, the best known of which is the genus 

 Carica. The latex occurs as a finely granular protoplasmic-like sub- 

 stance, which contains the peptonizing ferment papain, in articulated 

 laticiferous tubes, which occur in the pith, cortex and xylem of roots 

 and stems and are associated with the vascular bundles in leaves, 

 even penetrating into the mesophyll. Guignard has found, in cer- 

 tain tannin and laticiferous cells, a ferment resembling myrosin and a 

 glucoside agreeing with sinigrin, which occurs in black mustard seeds. 

 In many of the parenchyma cells, Ruger has observed large granules 

 of a spheroidal or irregular shape and strongly refractive, which are 

 supposed to be one of the aldehydes. The pericycle is composed of 

 isolated groups of bast fibers. The tracheae are marked by simple 

 pores or reticulate and scalariform thickenings. The medullary rays 

 and wood fibers are replaced apparently with parenchyma. 



CARICA. Papaw, Pawpaw or Papaya. The desiccated latex 

 of the fruit of Carica Papaya (Fam. Caricacese), furnishes a com- 

 mercial article, which contains one or more proteolytic ferments. 

 The seeds and leaves of this plant are also used to some extent in 

 medicine. 



The Papaw is a shrub (Fig. 197), indigenous to tropical America, 

 also occurring in southern Florida, and has become naturalized in 

 most of the tropical countries of the Old World. The trunks ma}' 

 attain a height of 4 or 5 M. and a thickness of 15 cm. The trunk 

 persists for a few years and is replaced by new shoots, which develop 

 from a more or less fleshy rootstock. The leaves are long petiolate, 

 yellowish-green, from 45 to 60 cm. in diameter, consisting of from 5 to 

 7 lobes, the latter being more or less deeply divided into nearly entire 

 lateral lobes. The veins and petioles are yellow or orange colored, 

 the latter being hollow and frequently 1 mm. in length; the flowers are 

 yellow, monoecious and are produced continuously throughout the 

 year. The staminate flowers are fragrant, contain large quantities 

 of nectar, and are borne in long racemose cymes. The pistillate 

 flowers are about 2.5 cm. in length and occur 1 to 3, ,in short-stalked 

 cymes. The fruits are formed in clusters at the base of the leaf 

 stalks. They are ovoid or ellipsoidal, obtusely short pointed, and 

 vary in color from yellowish-green to bright orange. The fruits of 

 the plants of southern Florida are usually not more than 10 cm. in 

 length. The fruits of tropical plants may attain a length of 30 cm. 

 and weigh 4 or 5 K. The epicarp is thick, and adheres to the orange- 



