154 ROSE FAMILY 



petals 5, spreading; styles 3-5, united at the base; ovary woolly, pome 

 small, berry-like. 



A North American genus of two species, probably not to be separated 

 from the genus P y r u s. Besides the following species, another occurs in 

 the eastern part of the United States. 



Aronia nigra (Willdenow) B r i 1 1 o n 1894 Black Chokeberry 

 Pyrus nigra Sargent 1890 



A branching shrub 1-1.5 meters (3-5 ft.) high, bark smooth grayish; 

 leaves from broadly oblong and acuminate to spatulate-oblanceolate, 

 finely glandular serrate, narrowed at the base, acute or mucronate at the 

 apex, glabrous or nearly so on both surfaces, 2-7 cm. long, 1-2.5 cm. wide, 

 petiole 5-6 mm. long; corymbs 3-5 cm. long, several-flowered, flowers 

 white, 10-12 mm. broad; calyx and pedicels slightly tomentose or soon 

 becoming glabrous; petals ovate, 4-5 mm. long; fruit a globose pome, 

 6-8 mm. in diameter, black or purplish : nigra, black, from the color of 

 the fruit. (See Fig. page 147.) 



In swamps and moist ground, occurring in the eastern part of the 

 state from Olmsted county northward. Distributed from Nova Scotia to 

 western Ontario, south to Florida and Minnesota. Flowers in May and 

 June, fruits in August. 



Crataegus Linne 1753 



(Gr. krataigos, the hawthorn tree, from k r a t o s, strength, re- 

 ferring to the wood) 



Thorny shrubs or small trees, with alternate, simple, usually lobed 

 leaves ; buds small obtuse, 3-4 mm. long, scales imbricated ; flowers in 

 corymbs ; calyx tube cup-shaped or campanulate, adnate to the carpels, 

 5-cleft or divided; petals 5, rounded, white or rose color; stamens 5-25, 

 in 1-3 rows, anthers oblong, yellow or red ; ovary inferior, consisting of 

 1-5 carpels, styles distinct; fruit a small pome, yellow or red, flesh dry or 

 mealy, nutlets 1-5, each usually 1 -seeded. 



A large genus, widely distributed throughout the temperate regions 

 of the northern hemisphere. The genus offers great taxonomic difficulties 

 and it is impossible at present to say how many species the genus includes. 

 Of late years numerous species have been segregated and described, but 

 it is very likely that when the group is thoroughly monographed a large 

 proportion of these will have to be withdrawn. 



