being supposed by Humboldt to be a derivative of "mapa," meaning 
honey. 1 
BOTANICAL RELATIONSHIPS. 
The plants of the genus Caiica have been referred to by different 
botanists to the families Papayaceae, Passifloreae, and Cucurbitaceae. 
This and the genus Jacaratia now constitute the family Caricacese. 2 
Carica has been divided into the three subgenera or sections, Vas- 
concellea, Hemipapaya, and Eupapaya, embracing 22 known species, 
all of American or West Indian origin, the genus being represented 
from Argentina to Mexico and in the Antilles. Of the home and 
probable origin of C. papaya, mention will be made later. 
DESCRIPTIONS OF FORMS OF PAPAYA. 
The above will serve to indicate the general botanical position of the 
papaya and its relatives. Breeding at this station has been confined 
chiefly to the one species of this genus C. papaya, C. peltata, and 
C. quercifolio. having been the only others used. Some descriptions 
of the forms in which the papaya itself occurs with reference chiefly 
to the distribution of the sexes and the shape of the fruit are given 
below. 
Form 1. The first form to be considered is the ordinary female. 
Commonly the papaya is dioecious. The female tree produces flowers 
exclusively pistillate, with no indication of even the remnants of 
stamens (PI. Ill) . At first sight they may appear to be polypetalous, 
since the corolla tube is greatly reduced, but closer observation re- 
veals their gamopetalous condition. The ovaries and the resulting 
fruits are of various shapes, inclining to the obovoid, with a diameter 
somewhat shorter than the major axis, and the surface smooth or only 
slightly ribbed. The fruits are usually borne singly on very short 
peduncles in the axils of the leaves. 
Form 2. The male tree (PL IV, fig. 1), the counterpart of that just 
referred to, produces only staminate flowers which, however, possess 
rudimentary or abortive pistils (PL IV, fig. 2), and hang in great pro- 
fusion in cymose panicles on peduncles, 2 to 5 feet in length. The 
flowers, unlike those of the female tree, have a long corolla tube in the 
throat of which are 10 stamens arranged in two series, the one having 
slightly longer filaments than the other. At the base of the tube 
may be found a small rudimentary pistil, quite devoid of any stigma. 
Since all the flowers are of this type the tree abounds in pollen, but 
produces no fruit. In foliage and habit, other than as described, it 
resembles the female. 
i Jour. linn. Soc. [London], Bot., 10 (1809), p. 14. 
>H. Solms-Laubach. Caricacee. In Martins, Flora Braailienais, vol. 13, pt. 3, col. 171-190, 
