APOCYNACEAE 249 



6. BARTONIA Muhl. 

 Corolla yellowish, 3-4 mm. long. i. B. Virginica. 



Corolla purplish, 4-5 mm. long. 2. £. iodandra. 



1. Bartonia Virginica (L.) B.S.P. Yellow BarTonia. (Man. p. 

 735 ; I. F. /. 2887.) In moist soil, Newf. to Fla., Mich, and La. — Penn- 

 sylvania : Lackawanna ; Monroe ; Schuylkill ; Bucks ; Mont- 

 gomery ; Delaware ; Chester ; Lancaster ; Franklin ; Hunting- 

 don ; Centre. 



2. Bartonia iodandra Robinson. (Man. p. 735.) In sphagnum, 

 Newf. to Pa. and N. J. — Pennsylvania. Specimens doubtfully referred 

 here have been found in Northampton County. 



Family 4. MENYANTHACEAE G. Don. Buckbean Family. 



Leaves with 3-foIiolate blades : swamp plants. i. Menyanthes. 



Leaves with simple blades : floating plants. 2. Limnanthemum. 



1. MENYANTHES L. 



1. Menyanthes trifbliata L. Buckbean. Marsh Trefoil. (Man. 

 p. 736; I. F. / 288g.) In bogs, Greenland to Alaska, L. L, Pa., Neb. 

 and Calif. Also in Eu. and Asia. — Pennsylvania : Susquehanna ; Mon- 

 roe ; Tioga ; Bucks ; Lancaster ; Centre ; Crawford ; Erie. 



2. LIMNANTHEMUM S. G. Gmel. 

 1. Limnanthemum lacunosum (Vent.) Griseb. Floating Heart. 

 (Man. p. 736 ; I. F. /. 2Sgo.) In ponds, N, S. to Fla., Ont., Minn, and 

 La. — Pennsylvania : Bucks, Bristol ; Pike, Twelve Mile Pond and Silver 

 Lake. 



Family 5. APOCYNACEAE Lindl. Dogbane Family. 

 Leaves alternate. i. Amsonia. 



Leaves opposite. 

 Flowers axillary to leaf-like bracts. 2. Vinca. 



Flowers in terminal cymes. 3. Apocynum. 



1. AMSONIA Walt. 

 1. Amsonia Amsonia (L.) Britton. Broad-leaved Amsonia. (Man. 

 p. 737-) In moist soil, Pa. to Mo., Ky., Fla. and Tex. — Pennsylvania: 

 Chester, West Grove. 



2. VINCA L. 

 1. Vinca minor L. Periwinkle. Myrtle. (Man. p. 738 ; I. F. /. 

 28g4.) Escaped, Ont. to N. Y., Conn., N. J. and Ga. — Pennsylvania: 

 Lancaster ; Allegheny. 



3. APOCYNUM L. 



Corolla 5-9 mm. long, the lobes recurved or spreading. 



1. A. androsaevtifolium. 

 Corolla 3-4.5 mm. long, the lobes erect or nearly so. 



Corolla greenish white : leaf-blades 2-4 times as long as wide. 



2. A. cannabimim. 

 Corolla white : leaf-blades 4-6 times as long as wide. 



3. A. album. 



