Trees of New York State 369 



short filaments and elongate elavate anthers crowTied with a pilose, truncate, 

 connective; pistillate heads green tinged with red, solitary and terminal or in 

 terminal spicate clusters, the lateral heads then embracing the peduncle at 

 maturity; sepals 3-6, rounded; petals 3-6, acute, longer than the sepals; 

 staminodia present; pistils 3-6, superior subtended at the base with per- 

 sistent straight hairs, with long curved styles stigmalic on the ventral side. 

 Fndt a subgobose head, consisting of many clavatc, crustaccous 1-seeded 

 aclienes tipped with the persistent styles and subtciidcd at the Ijase with bristly 

 liairs; seed oblong, albuminous. 



THE PLANE TREES. Gonu.s PL AT ANUS (Toiirn.) L. 



For (lislrJl)ul ion ;ni(l cliaractcrs of the fjcnns, see description of 

 Die family. 



ROSE FAMILY. ROSACEAE 



Trees, slirubs and a few herbs numbering upwards of fifteen 

 hundred species, gTouped in about ninety genera. Rosaceous 

 phmts are widely distributed throughout the temperate regions of 

 the world and include many of our important fruit trees such as 

 the Apple and the Pear. Ten genera are represented by arbores- 

 cent s})ecies within the United States. 



Sap watery. Branchlcts terete. Buds scaly Leaves alternate or rarely 

 opposite, simple or compound, deciduous or persistent, stipulate. Flowers 

 perfect, generally showy; calyx-tube 5-lobed; petals 5 and separate, or want- 

 ing ; stamens numerous, distinct, inserted with the petals on a disk lining 

 the calyx-tube ; anthers small, 2-celled, longituduially dehiscent ; pistils 

 1-many, distinct or united and combined with the calyx-tube; ovules 1-2 in 

 each cell. Fruit various. 



KEY TO THE GENERA page 



1 . Ovary inferior, 2-5 celled, adnate to the enlarged calyx-tube (or receptacle) ; 



fruit a pome 2 



1. Ovary superior, 1-celIed; fruit a drupe Prunus 371 



2. Mature carpels papery or soft-cartilaginous at maturity 3 



2. Mature carpels hard and bony at maturity Crataegus 371 



3. Cells of the ovary as many as the stvles, without false partial partitions 



Pyrus 3 9 

 3. Cells of the ovary twice as many as the styles, with false partial partitions . . 



Amelanchier 370 



THE APPLES AND PEARS. Genus PYRUS (Tourn.) L. 



Small or medium sized trees of the northern hemisphere, chiefly 

 of the Old World. Some forty species are included, of which five 

 are native to North America, four in the eastern states and one 

 on the Pacific Slope. In addition several introduced species have 

 uccome widelv naturalized. 



