328 Karl M. Wiegand and Arthur J. Eames 



2. C. florida L. Flowering Dogwood. 



Dry sandy, gravelly, or rocky woodlands, mostly in acid soils ; frequent. May. 



Generally distributed in the upland woods on the hills w., s., and s. e. of Ithaca, 

 on the ravine crests, and along the cliffs of the Cayuga Lake shore; absent in the 

 McLean district and on the clays and richer soils. 



S. Me. and Ont. to s. Minn., southw. to Fla. and Tex., including the Coastal Plain. 



3. C. rugosa Lam. (C. circinata of Gray's Man., ed. 7, and of Cayuga Fl.) Round- 



leaved Dogwood. 



Dry gravelly or rocky open woodlands, thickets, and banks, often in clay, in neutral 

 or slightly acid soils; frequent. June 10-30. 



Fairly common on the hills w., s., and s. e. of Ithaca, along the ravines, and on the 

 cliffs of Cayuga Lake shore; absent on the calcareous gravels of the McLean region, 

 on the richer soils, and apparently also on the more acid soil of ericaceous-chestnut 

 woodlands. 



E. Que. to Man., southw. to Va., Ind., 111., Iowa, and N. Dak. ; rare or absent on 

 the Coastal Plain. 



Lamarck's C. rugosa is clearly this species, and antedates by two years C. circinata 

 L'Her. (See publications by Wangerin, Britton and Brown, Schneider, and Rehder.) 



4. C. Amomum Mill. (C. sericea of Cayuga Fl.) Silky Dogwood. Kinnikinnik. 



Low grounds in alluvial or gravelly soils, without apparent relation to lime, but not 

 actually in peat bogs; common. June 15-July 10, and often again July 25-Aug. 5. 



Newf. to N. Dak., southw. to Fla., La., and Tex. ; fairly common on the Coastal 

 Plain. 



5. C. stolonifera Michx. Red Osier Dogwood. 



Low grounds and springy upland places, in gravelly or sandy, more or less cal- 

 careous, soils ; common, and generally distributed in the soils indicated. May 25- 

 June 15, and often again July 25-Aug. 5. 



Lab. to Mackenzie, southw. to Va., Ky., Iowa, Nebr., N. Mex., Ariz., and Calif. ; 

 rare or absent on the Atlantic Coastal Plain. 



Sometimes united with C. alba L, but, though closely related, the differences are 

 sufficient to warrant the recognition of both species for the present. The form with 

 vellow twigs (var. flaviramea Spaeth) has escaped to roadsides north of Enfield 

 Falls. 



6. C. candidissima Marsh. (C. paniculata of Gray's Man., ed. 7, and of Cayuga 



Fl. C. racemosa of Bailey's Man. Cult. PI.) 



Dry or damp thickets, fence rows, and hillsides, in gravelly or alluvial, mostly 

 neutral, soils often with a slight mixture of clay ; common. June 25-July. 



Common about Ithaca, but somewhat less so in the residual soils on the hills. 



Cent. Me. to Ont. and Minn., southw. to N. C, Tenn., and Nebr. ; less common on 

 the Coastal Plain. 



Until it is decided whether C. foemina Mill, was C. paniculata L'Her. or the 

 southern C. stricta, that name is to be avoided. C. candidissima Marsh., the next 

 oldest name, is valid under the International Rules. 



7. C. alternifolia L. f. Alternate-leaved Dogwood. 



Damp thickets and ravine banks, in gravelly or stony soils with little reference to 

 lime content ; common. June. 



Newf. to Minn., southw. to Ga., Ala., and Mo. ; frequent along the coast. 



