FLORA OF THE DISTRICT OF COLUMBIA. 255 



1. LEPTAMNITJM Raf. 



1. Leptamnium virginianum (L.) Raf. Beechdrops. 



Paraaitic on roots of the l)eec]i in moist woods; common. Aiig.-Oct; Eastern N. 

 Amer. (Epiphagus virginiana Barton.) 



2. THALESIA Raf. 



1. Thalesia uuiflora (L.) Britton. Ghost-pipes. 



Moist woods and thiclcets; common. May. Eastern N. Amer. {Aphjllon uni- 

 florum Torr. & Gray.) 



A tuft of the plants is shown in plate 37 A. 



3. CONOPHOLIS Wallr. 



1. Conopholis americana (L. f.) Wallr. Squaw-root. 



Rich hilly woods; common. May. Eastern N. Amer. 

 A tuft of the plants is shown in plate 34 A. 



4. OROBANCHE L. 



1. Orobanche minor J. E. Smith. Broom-rape. 



Parasitic on clover; common. May- June. N. J. to Va.; naturalized from Eur. 



140. PINGUICUMCEAE. Bladderwort Family. 



Plants growing in water, the stems creeping or floating, branched. Bracts of the stems 



attached by the base 1. UTRICULARIA. 



Plants growing in soil, the stems erect, simple. 

 Bracts of the stems attached by the middle ; bracts at the base of the pedicel without 



bractlets; calyx not inclosing the capsule 2. SETISCAPELLA. 



Bracts attached by the base; bracts at the base of the pedicel accompanied by a 

 pail' of bractlets; calyx inclosing the capsule 3. STOMOISIA. 



1. XJTRICTJLARIA L. BladderWort. 



Stems creeping in the bottom of water; corolla 4-6 mm. long; flowers 1-4 on each 

 scape 1. TJ. gibba. 



Stems free-floating except for a single point of attachment; corolla 13-20 mm. long; 

 flowers 6-20 on each scape 2. U. macrorhiza. 



1. Utrlcularia gibba L. 



Poolsalong the upper Potomac. July-Sept. Eastern N. Amer. 



2. TJtricularia macrorhiza LeConte. Zigzag bladderwort. 

 Hunting Creek. Aug. Widely distributed in N. Amer. {U. vulgaris oikvaexicscD. 



authors.) 



2. SETISCAPELLA Barnhart. 



1. Setiscapella subulata (L.) Barnhart. 

 Wet sandy soil; occasional. May-July. Eastern U. S. (Utriailaria subulata L.) 



3. STOMOISIA Barnhart. 



1. Stomoisia virgatula Barnhart. 

 Swamp near Suitland. N. Y. to Miss. ( Utriadaria virgatula Barnhart.) 



141. ACANTHACEAE. Acanthus Family. 



Flowers in dense long-stalked heads or spikes, small; plants glabrous; leaves linear- 

 lanceolate 1. DIANTHERA. 



Flowers borne in the axils of the leaves, large; plants more or less hairy; leaves ovate 

 or oblong 2. RUELLIA. 



