FRUITS 89 
Fic. 94.—Peach (Prunus Persicgq, Rose Family, Rosacee). A, flowering 
branch. 8, 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. HE, fruit with flesh cut in half vertically, showing the 
rough “‘stone”’ or inner hardened part of the ovary wall. F, the “‘stone’”’ 
broken in half to show the single seed within. (LeMaout and Decaisne.) 
The plant is a tree; leaves smooth; flowers pink, appearing before the 
leaves; fruit downy. 
As already intimated, the most significant features of the 
chemical composition of fruits are (1) the presence in con- 
siderable amount of peculiar acids, (2) the predominance 
of sugar in the dry substance, and (8) 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 be 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 
