CLASSIFICATION. 57 



III. Peak Subfamily. — Consists of shrubs or trees, with 

 stipules free from the petiole; the thick-walled calyx-tube be- 

 ^ coining fleshy or pulpy and consolidated with the 2-5 ovaries to 

 form a compound pistil and the kind of fruit called a pome. 

 Lobes of, the calyx and petals 5. Stamens niunerous, or rarely 

 only 10-15. 



4. Ptrus. Trees or shrubs, sometimes rather thorny, with various 

 foliage, and flowers in cymes, corymbs, or rarely solitary. Styles 2-5. 

 Ovary of 2-5 two-ovuled (or in cultivated species, and in Cydonia, sev- 

 eral-ovuled) cells, which are thin and papery or cartilaginous in fruit 

 in the fleshy or pulpy calyx tube. 



THE DRUPES. 



GENUS PRUNUS. 



(The ancient Latin name of the Plum.) 



Shrubs or trees, mostly with early and showy flowers. 



The genus contains about Y5 species of shrub's and trees 

 widely distributed in the north temperate zone. It includes 

 several well marked groups — peaches, plums, cherries, almonds, 

 nectarines and apricots — some of which are regarded as dis- 

 tinct genera by many botanists. The best authorities are now 

 pretty well agreed that because of the great number of inter- 

 gradient forms it is best to include the above fruits in one 

 genus. The horticulturists are rapidly obliterating existing 

 differences by means of hybridization. Horticulturally, 

 Prunus is one of the most important of all genera. It contains 

 many valuable ornamentals besides the fruits discussed here. 

 Eor our purposes we may divide the genus into four main 

 groups as follows : 



1. Peaches and almonds. 3. Plums. 



2. Apricots. 4. Cherries. 



