504 BOTANICAL SURVEY OF DISMAL SWAMP REGION. 



Epidermis: Alike on both faces, cells containing chlorophyll, rather 

 large, with thin, undulate radial walls and thickish wrinkled cuticle. 

 Stomata confined to the dorsal surface, small, lying in all directions, 

 level with the surface, each bordered by usually four epidermis cells, 

 of which two are subsidiary (parallel to the guard cells but not other- 

 wise differentiated). Hairs few on Ihe ventral, numerous on the 

 dorsal surface, soon deciduous, pointed, with rather thick, rough 

 cuticle, pluricellular (the cells in a single row). 



Palisade in a single layer, the cells high. Pneumatic tissue rather 

 open. 



Hypodermal eollencliyvia strongly developed above and below the 

 m id vein. 



Stereome both above and below the veins (especially adjoining the 

 leptoiue). 



STYKAX UKAND1FOLIA Ait. 



Mixed Forest formation, growing in low woods. 



Leaf large, thin, bifacial, pubescent beneath. 



Epidermis: (-ells alike on both faces, the radial walls st rongly undu- 

 late; cuticle delicately wrinkled. Stomata only on the dorsal face, 

 small, comparatively few, lying in all directions, level with the surface, 

 each bordered by four to seven undifferentiated epidermis cells. Hairs 

 confined to the dorsal surface, more or less abundant, especially along 

 the veins, long, sharp-pointed, thick-walled, unicellular. 1 



Mesophyll not well differentiated, two layers of compact but not 

 elongated cells beneath the ventral epidermis, the rest open pneu- 

 matic tissue with large unicellular spaces. 



HypodermalcoUenchy malic tissue in small quantity above the large 

 veins. True collenchyma in corresponding position below the veins. 



Stereonte none. 



Chionanthus virginica L. 



Ilygrophile Forest formation, inhabiting swampy woods along 

 streams. 



Leaf large, bifacial, green on both surfaces, becoming somewhat 

 coriaceous, glabrous when mature, pubescent on both surfaces, but 

 especially beneath, when young. 



Epidermis: Ventral, cells small with thickish walls, the radial walls 

 not undulate; cuticle strongly wrinkled. Dorsal, cells with straight 

 or slightly undulate radial walls; cuticle with more numerous finer 

 wrinkles. Stomata confined to the lower surface, very numerous, 



1 It does not appear that unicellular hairs have been previously noted in this 

 family (cf. Solereder Syst. Anat., 587). / 



