21 



into tubes at the apex, opening by terminal pores or chinks. 

 Pistil single, with a 4-5 or 8-10 celled ovary which is glabrous 

 or hirsute. Flowers in spring with or before the leaves, berries 

 ripe in summer and autumn, sweetish or sometimes acid, mostly 

 edible. 



THE NATURAL GROUPS OF SPECIES. 



In making the following natural divisions of the genus I have, 

 in general, followed Bentham and Hooker, but have included 

 the group Oxycoccus, after Gray in Synoptical Flora. When 

 two closely related forms occur over a wide range in latitude, 

 the assigned differences are very liable to fail at some point. 



Key to the Groups. 



A. Ovary, 4-5 celled (rarely 8-10 celled in Vitis-Idaea). 

 B. Stamens exserted 



C. Filaments villous OxycoccoidES. 



CC. Filaments puberulent Oxycoccus. 



BB. Stamens included 



C. Filaments glabrous or pubescent Euvaccinium. 



CC. Filaments pilose Vitis-Id^a. 



AA. Ovary 10 celled (sometimes imperfectly so in Cyanococcus). 

 B. Anthers with two awns on the back. . . Batodendron. 

 BB. Anthers awnless Cyanococcus. 



OxycoccoidES, B. & H. 



Erect branching shrubs with deciduous membranaceous leaves 

 and berries of Euvaccinium, but with corolla of true Oxycoccus: 

 flowers solitary, axillary, on long pedicels, pedicel bractless, but 

 minutely 2-bracteolate at the base. V. erythrocarpon 



V. Japonicum 

 Oxycoccus. (Oxycoccus, Pers.) Gray. 



Corolla deeply 4-cleft or 4-parted ; the lobes linear or lanceo- 

 late-oblong, reflexed ; stamens 8, exserted, anthers awnless, with 

 very long terminal tubes ; ovary and berry 4-celled ; flowers, pale 

 rose-colored, axillary and terminal, nodding on long filiform 

 pedicels ; appearing in early summer ; fruit maturing in autumn. 



C. Stems very slender, creeping V. Oxycoccus 



CC. Stems stouter, with ascending branches 



V. maorocarpon 



