Cross. — Observations on some New Zealand Halophytes. 561 



submerged (tig. 9, a) : The stems are longer, reaching a le^igth of 40 cm. 

 They are narrower, less rigid, and are generally vinbranched. Leaves 

 (fig. 9, e-f) also are longer and narrower (9-12 cm. long, 2-5 mm. broad), 

 ribbon-like or finely dissected ; they are extremely delicate, so that they 

 droop immediately on being removed from the water. Roots are given off 

 from the nodes right up the stem, except towards the upper end ; they 

 are very long, have few rootlets, absolutely no root-hairs, and the upper 

 ones are slightly green. 



Fig. 9, g shows a floating leaf, which is broader than the submerged 



ones. 



Anatomy. 



No account of the anatomy of the first four species is given, for the 

 reason prefixed to the last section of the paper. With regard to the other 

 species, in most instances the anatomy of the leaf only is described, or of 

 the stem when leaves are absent. 



5. Leptocarpiis simplex. 

 Stem. 



Epidermis has a cuticle of great thickness. In T.8. this has an appar- 

 ently cellular structure (fig. 10, a), but, as it assumes a yellowish-brown 

 colour with chlor-zinc-iodide, it is assumed that cutin is present. Then, 

 again, by taking longitudinal sections, it is seen that the apparently cellular 

 structure is due to irregularity in the laying-down of the thickening layers, 

 each of which has a wavy outline (fig. 10, b). 



The stomata occur over the bands of chlorenchyma, and are small, and 

 sunk below the rest of the epidermis.. In T.S. two small subsidiary cells 



appear. In most cases the 

 edges of the cuticle almost 

 meet over them, so that 

 they can scarcely be seen in 

 surface-view. 



Chlorenchyma in definite 

 bands 3-4 layers deep, and 

 6-7 cells wide. The cells are 

 of the regular pahsadic type, 

 with somewhat numerous 

 and rather large chromato- 

 phores. 



Sclerenchyma : Narrow 

 bands of thick- walled cells, 

 alternating with the bands 

 of chlorenchyma. 



The f.v. bundles are in 

 three fairly regular circles, 

 the larger ones towards the 

 inside, while the outermost 

 circle is formed of tiny 

 bundles, one beneath each 

 band of sclerenchyma. Each 

 bundle has a mass of sclerenchyma at its upper end, and this sclerenchyma 

 is continued round to form a complete circle, in which the outer bundles are 

 embedded. There is a small amount of phloem in the bundle, and a 



cict. 



Fig. 10. — Leptocarpus simplex. 



a. T.S. of epidermis, showing cuticle ; highly 

 magnified, b. L.S. of epidermis showing 

 cuticle ; highly magnified. 



