Ill 



21a. Leaves green beneath Snowberry, Symphoricarpus racemosus. 

 21b. Leaves whitened beneath 



Snowberry, Symphoricarpos racemosus yar. pauciflorus. 



22a. Leaves palmately lobed 23. 

 22b. Leaves not lobed 25. 



23a. Outermost flowers of the cluster enlarged and imperfect (1 4 

 m. high) Cranberry Tree, Viburnum opulus var. americanum. 



23b. All flowers of the cluster alike 24. 



24a. Flower-clusters 4 10 cm. broad (1 2 m. high) 



Arrow Wood, Viburnum acerifolium, 



24b. Flower-clusters 2 3 cm. broad 



Squashberry, Viburnum pauciflorum. 



25a. Outer flowers of the cluster enlarged and imperfect (1 3 m. 

 high) Hobble-bush, Viburnum a I n if o I mm. 



25b. All flowers of the cluster alike 26. 



26a. Leaves finely serrate; the veins not prominent 27. 

 26b. Leaves coarsely serrate, all or most of the teeth terminating 

 in a prominent vein 29. 



27a, Peduncle of the flower-cluster, below its branches, at least 2 cm. 

 long (1 3 m. high) Withe-rod, Viburnum cassinoides. 



27b. Peduncle of the cluster 1 cm. long, or even shorter (3 8 m. 

 high) 28. 



28a. Leaves distinctly acuminate 



Sheep-berry, Viburnum lentago. 

 28b. Leaves obtuse or barely acute 



Black Haw, Viburnum prunifolium. 



29a. Leaves densely pubescent beneath (6 15 dm. high) 



Arrow-wood, Viburnum pubescens. 



29b. Leaves glabrous beneath, or with tufts of hairs in the forks 

 of the veins (1 4 m. high) Arrow-wood, Viburnum dentatum. 



VALERIANACEAE, the Valerian Family 



Herbs with opposite leaves and small nearly or quite regular 

 flowers; petals 5, united; stamens 3; sepals minute or wanting; ovary 

 inferior. 



la. Stem-leaves pinnately cleft (310 dm. high; flowers white or 



pinkish, summer) 2. 



Ib. Stem-leaves entire or dentate (26 dm. high; flowers white, sum- 

 mer) (Corn Salad) 3. 



2a. Leaf-segments parallel-veined Valerian, Valeriana edulis. 

 2b. Leaf-segments net-veined 



Swamp Valerian, Valeriana uliginosa. 



3a. Upper stem-leaves entire Corn Salad, Valerianella chenopodifolia. 

 3b. Upper stem-leaves dentate Corn Salad, Valerianella radiata. 



