270 



BOTANICAL GAZETTE 



[OCTOBER 



pointed hairs on the upper surface; chlorenchyma, a layer of pali- 

 sade, and a layer of spherical cells about the bundles; walls of 

 parenchyma cells sometimes folded in as in Pinus; stomata sunken 

 as in Ammophila. Stem with bundles more numerous toward the 

 periphery, where the cells of the fundamental tissue become 

 smaller; epidermal cells very small. 



Solidago racemosa Gillmani (fig. 1). — A perennial herb, woody 

 at the base. Leaf with outer wall of lower epidermis 8 /* thick, 



cuticle 2 . 4 ft; chlorenchyma above 

 and below; water-storage tissue in 



the center; chlorenchyma above 

 scarcely palisade-like, but of two 

 or more layers of slightly elongated 

 cells forming a compact tissue; 

 good development of bundles in 

 the midrib. Stem with small pith; 

 cortex thick, containing groups of 

 fibers and occasionally sclereids, 

 outer layers collenchymatous; 

 crystals in the cells of the pith. 

 Root with ground tissue of scle- 

 renchyma; outer cells of cortex 

 collenchymatous. 



Lithospermum Gmelini. — A per- 

 ennial herb clothed with bristly 

 hairs. Leaf thick, coarse, rough on both surfaces, with appressed 

 hairs, bent upward at the midrib; outer wall of epidermis thick 

 on both surfaces, 9.3/*; palisade next both epidermal layers made 

 up of a row of long cells, or of two rows of shorter cells; three layers 

 in the center almost colorless; stomata not sunken. Stem with a 

 small solid cylinder of wood made up chiefly of fibers, the vessels 

 large; outer layers of cortex slightly collenchymatous; outer wall 

 of epidermis 5 fi thick. 



Arenaria stricta. — A low, tufted herb. Leaf smooth, needle- 

 like; epidermal cells enormous, thickened on all sides especially at> 

 the edges of the leaf; outer wall 3.2-7 f*; cuticle thick; scleren- 

 chyma below the bundles; whole mesophyll composed of compact 

 tissue; no palisade; crystals frequent. 



Fig. i. — Solidago racemosa Gill- 

 mani: section of leaf. 



