FLORA OF THE DISTRICT OF COLUMBIA. 261 



2. Viburnum afflne Bush. 



Frequent on rocks and in woods on both sides of the river about Great Falls. May , 

 fr. July-Sept. Northeastern N. Amer. 

 Our plant is the pubescent form, 7. a#n, %pomalacum Blake. (7. pu6««n. of 



authors.) 



3. Viburnum dentatum L. . w«-rt, 



Common in moist ground and swamps. May-June; fr. July-winter. North- 



eastern IT. S. 



4. Viburnum scabrellum (Torr. & Gray) Chapm. 



Common; in drier land, fence rows, and edges of woods. June. Southeastern U . B. 



5. Viburnum pubescens (Ait.) Pursh. 



Common in copses and fence rows. June; fr. Aug.-wmter. Eastern U. B. ( K. 

 v«no«m Britton; V. venomm canbyi Render.) 



This and the last preceding are closely related to V. dentatum and puzzling inter- 



mediate forms occur. 



6. Viburnum cassinoides L. 



In bogs now or formerly sphagnous; north and east of Washington. May-June, 



fr. Aug.-winter. Eastern N. Amer. 



7. Viburnum nudum L. 



With the last, but also in ordinary swampy or wet places. May-June; rr. Sept. 



May. Eastern U.S. 



., ,. t Black haw. 



8. Viburnum prunifolium L. 



Abundant in a variety of situations. Apr.-June; fr. July-Apr. Eastern U. S. 

 A shrub, or a small tree with trunk as much as a foot in diameter. 



6. SAMBUCUS L. 



. , T Elder. 



1. Sambucus canadensis L. 



Abundant in wet places. May-June; fr. July-Aug. Eastern N. Amer. 



146. VALERIANACEAE. Valerian Family. 



Plants perennial, spreading by slender runners; stem leaves pinnate; corolla very 



, . , , M ...1. VALERIANA. 

 slender, 1-2 cm. long - 



Plants annual; stem leaves narrow, simple; corolla 2-3 mm. long. w __„„___ . 



2. VALEBIANELLA . 



1. VALERIANA L. Valerian. 



1. Valeriana pauciflora Michx. 



Shaded alluvial flats; locally common at a few localities along the Potomac from 

 High Island to Plummers Island, especially on the islands. May. Eastern U. B. 



2. VALEBIANELLA Hill. Lamb's lettuce. Corn salad. 

 Corolla bluish, the color evident in the subpersistent corollas of fruiting specimens. 

 Fruit flattened, rounded 



Corolla whitish. j„i QT ,a 



Fruits roundish or saucer-shaped, the sterile cells inflated 2. V. wooasiana. 



Fruits oblong to ovate in outline. . 



Fertile cell of the fruit distinctly broader than the sterile one, the fruit triangular 



3. V. chenopodifolia. 



in cross Bection 



Fertile cell as broad as the sterile ones, the fruit 4-angled m cross section. 



4. V. rauiata. 



1. Valerianella locusta (L.) Betcke. 

 Damp meadows, old fields, and thickets; not uncommon, ejjfefcfly atang the 



Potomac. Apr .-May. Naturalized from Eur. (Fedia olitona of W ard s Flora.) 



