14 LEITNERIACEAE. 



LEITNERIA. Corkwood. 

 ( Family Leitneriaceae ) . 



Little-branched tree-like shrubs 

 with very soft and light wood: 

 deciduous. Twigs round, rather 

 stout: pith moderate, rounded, 

 continuous, white. Buds solitary, 

 sessile, rather small, ovoid, with 

 about 3 exposed scales, or the up- 

 per (floriferous) enlarged, oblong, 

 or ellipsoid, and with a dozen or 

 more exposed scales. Leaf-scars 

 alternate, half-elliptical or some- 

 what 3-lobed, slightly raised: bun- 

 dle-traces 3: stipule-scars lacking. 

 The North American corkwood, 

 apart from the fact that its wood 

 is very much lighter than that 

 of any other native shrub or tree, 

 is interesting in that it is the only 

 representative of its family, not 

 very closely related to any other 

 group, and that it occurs locally 



in swamps from western Florida, where it was first found, to 

 southern Missouri, apparently surviving from a time when 

 the Mississippi carried much more water and spread over a 

 greater delta than at present. Like the bald cypress, though 

 occurring naturally in swamps, it is capable of successful cul- 

 tivation in soil of ordinary dryness. 



On anatomical grounds, Van Tieghem and Lecomte, in 

 the Bulletin de la Societe botanique de France, 33:181, ally 

 Leitneria with Dipterocarpaceae. Dr. Pfeiffer, in the Botani- 

 cal Gazette, 53:119, finds in it a suggestion of derivation of 

 catkin-bearing angiosperms from gymnosperms. 

 Loosely gray-hairy: twigs purplish. L. floridana. 



