236 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



5. Phlox pilosa L. 



Evidently rare or overlooked with us; Woodley Park; Herndon; Chevy Chase. 

 May. Eastern U. S. . 



The annual phloxes of gardens are cultivated strains of the Texan P. drummondii 

 Hook. 



132. HYDK0PHY1LACEAE. Waterleaf Family. 



Calyx conspicuously enlarged in fruit, without appendages between the lobes, broad 



and saucer-shaped; capsule hanging. Leaves pinnately lobed 1. NYCTELEA. 



Calyx not conspicuously enlarged in fruit, with or without appendages between the 

 lobes, the lobes narrow and more or less appressed to the usually erect capsule. 

 Plants perennial, with large long-petioled basal leaves; placenta} expanded so as 

 to line the ovary wall, inclosing the ovules and seeds; leaves simple or pinnate. 



2. HYDROPHYLLTTM. 



Plants annual, with numerous small, short-petioled or sessile stem leaves but no 



. conspicuous basal leaves; placentae mere ridges on the ovary wall; leaves 



pinnately lobed 3 PHACELIA. 



1. NYCTELEA Scop. 

 1. Nyctelea ambigua (Nutt.) Standi. 



Low woods above the fall line. Apr.-May. Eastern X. A me r. (ElMa nyctelea L.; 

 Macrocalyx nyctelea Kuntze; N. nyctelea Britton.) 



2. HYDROPHYLLTTM L. Waterleaf. 



Leaves pinnately divided or lobed ; corolla pale lilac or lavender. . . 1. H. virginianum. 

 Leaves palmately 5-7-lobed, broad, cordate at base; corolla dirty white. 



. tt_j i. .. . . , , - 2. H. canadense. 



1. Hydrophyllum virginianum L. 



Low woods above the fall line. May. Eastern N. Am er. 



2. Hydrophyllum canadense L. 



Low woods above the fall line. June. Eastern U. S. 



3. PHACELIA Juss. 



Racemes 2-5-flowered; filaments not hairy; capsule wider than high, constricted 



around the 4 large seeds _ j, p covillei. 



Racemes several-flowered, noticeably uncoiling as the flower buds open; filaments 

 hairy; capsule ovoid, longer than wide. 

 Leaf lobes or divisions 3-5, the upper leaves not clasping; calyx lobes in fruit 4 mm. 



long; corolla lobes entire; seeds 6-12 2. P. dubia. 



Leaf lobes or divisions 5-9, the upper leaves clasping; calyx lobes in fruit 6-7 mm. 

 long; corolla lobes fringed; seeds 4 3, P, pU rshii. 



1. Phacelia covillei S. Wats. 



Rich woods along the upper Potomac; more common than either of the following 

 found in the same region. Apr.-May. Known definitely only from our region. * 

 The type was collected on Larkspur Island. 



2. Phacelia dubia (L.) Small. 



Rich woods. Apr.-May. Southeastern U. S. (P. parviflora Pursh.) 

 8. Phacelia purshii Buckl. 

 Rich woods. May-June. Eastern U. S. . 



