1909-] STRAND PLANTS OF NEW JERSEY. 81 



are vertical or nearly so. The contracted panicle of heads appears 

 from August to November. The thin-walled, upper epidermal cells 

 are approximately square in outline in the transverse view, only 

 the outer wall being somewhat thickened. Chlorenchyma cells 

 almost homogeneous, are directed vertically, hence the leaf is a 

 staurophyll. 



A triplex hastata (=^. patula var. hastata) (Plate IV, Figs. 

 9, ga, lo and loa). — The orache is an erect, or spreading, stout 

 plant and at least the lower leaves are broadly triangular, hastate, 

 often coarsely and irregularly toothed. The upper and lower epi- 

 dermal cells are large, thin-walled. The chlorenchyma of similar 

 elongated cells extends from the upper to the lower surface, so that 

 the leaf is a typic staurophyll. Large sphserocrystals are present 

 in the parenchyma cells of the leaf and the guard cells of the sto- 

 mata are considerably sunken beneath the surface (Figs, ga and 

 loa). The leaves of the specimen from Belniar were somewhat 

 thinner than those from Normandie and the chlorenchyma cells 

 were more rounded. 



Hudsonia tomentosa (Plate II, Fig. 2; Plate IV, Figs. 11, iia). 

 — The dunes are in many places covered with this heath-like plant 

 (Plate II, Fig. 2), which is an important sand binder, as it grows 

 in dense clumps. The small awl-shaped leaves are oval or narrowly 

 oblong and are close-pressed and imbricated, covered with a downy 

 tomentum. The epidermal cells of the leaves are thin-walled and 

 covered with slender, sharp-pointed hairs with a smooth cuticle. 

 The hairs are so numerous on both sides of the leaf, that they act 

 effectively in controlling transpiration. The guard cells of the 

 stomata are only slightly depressed (Fig. iia). 



Cenchriis tribuloides (Plate IV, Figs. 12, 12a and 12b). — The 

 sand bur grass branches extensively and sometimes has the trailing 

 habit. The blades are more or less involute, owing to the presence 

 of bulliform cells. The upper epidermal cells are marked by crys- 

 talline idioblasts (Fig. 12a) in an elongated form like the cystoliths 

 in the leaf of the rubber plant, Ficus elastica. The epidermal cells 

 on the under side of the leaf where the sclerenchyma occurs are 

 terminated by short cusp-like spines. The guard cells (Figs. I2h 



