FRUITS 



89 



Fig. 94. — Peach {Prunus Persica, Rose Family, Rosacea-). A, flowering 

 branch. B, flower, cut vertically. C, diagram of flower. D, ovary, 

 cut across to show the two layers of the wall, the outer (dotted) which 

 becomes fleshy, and the inner (white) which becomes hardened as the 

 "stone" or "pit"; and the two ovules of which only one commonly 

 becomes a seed. E, fruit with flesh cut in half vertically, showing the 

 rough "stone" or inner hardened part of the ovary wall. F, th(> "stone" 

 broken in half to show the single seed within. (LeMaout and Decaisne.) 

 The plant is a tree; leaves smooth; flowers pink, ajipoaring before the 

 leaves; fruit downy. 



As already intimated, the most significant features of the 

 chemical composition of fruits are (1) the presence in con- 

 sideralile amount of peculiar acids, (2) the predominance 

 of sugar in the dry substance, and (3) the presence of useful 

 salts. These chemical characteristics are shown on the chart. 

 It will also be noticed that the proportion of proteid is very 

 small except in the banana which, in this respect, is typical 

 of a certain class of tropical fruits, including the date and 

 fig, that form a highly important source of nutriment in the 

 regions where they grow. Starch may ])e detected in the 

 banana; in the more juicy fruits, however, starch is absent. 



The highly attractive flavoring matters upon which our 

 enjoyment of fruits largely depends, are present in such ex- 

 ceedingly small amount that chemical analysis can hardly 



