128 Botanisches Centralblatt. — Beiheft 2. 



sents a very peculiar aspect appearing as if intermixed with 

 stereome. None of tlie mestome-bundles showed the orbicular 

 outline, which is otherwise characteristic of these inhabitants of 

 dry plains and deserts- 



Our material of this grass was coUected in alkaline soil on 

 the plains of Colorado, but the leaf-structure is identical with tliat 

 of specimens from the sea-shore. In a previously published paper 

 (Botan. Gazette 1891. p. 275) we have described DistichUs from 

 various parts of this country, and the structure is in all impor- 

 tant points the same in plants from the salt-plains of the interior, 

 and in those from the salt marshes of the sea-board. 



Munroa squarrosa Torr. (Festuceae). 



This is like Buchlo'e and Schedonnardus one of the most 

 eharacteristie grasses of the plains. It is annual, but very much 

 branched and forms small, glaucous cushions of very rigid leaves, 

 while the flowers are barely visible, being hidden in the leaf- 

 sheaths. The culms are very short and the leaves crowded at the 

 apex, each supporting a minute brauch with a large proph3^11on, 

 of which the two nerves are extended into quite long stiff and 

 pungent awns, reüexed and divergent. 



The leaf as to its anatomy reminds us very much of that 

 of Buchlo'e, but has more stereome throughout, especially under- 

 neath the leptome and the colorless tissue. The blade is narrow, 

 furrowed on both faces, but the furrows are wide and shallow. 

 Hairs are absent, but pointed prickle like projections are scattered 

 on the Upper face, while the lower is slightly scabrous with short 

 papillae. The bulliform cells are quite large and cover a few 

 layers of colorless tissue. Stomata are distributed on both faces, 

 near the furrows. As stated above, the stereome is rauch better 

 represented in this grass than in Biichloe, but shows otherwise the 

 same distribution. The mestome-bundles are relatively small, all 

 orbicular and surrounded by a single layer of palisades, a large- 

 celled, thin walled and green parenchyma-bheath, and a mestome- 

 sheath with the inner cell-walls much thickened and porous in the 

 larger mestome-bundles. 



Scleropogon Karioinskianus (Fourn.) Benth. (Festuceae). 



This dioecious grass from the prairies of Texas is remark- 

 able for the very different aspect of the two sexes, which is so 

 great that without proof one would never suspect them to belong 

 to the same species. The Howering glume of the staminate spikelet 

 is only minutely three-toothed at the apex, while in the pistillate 

 plant it is provided with three very long, firm and sometimes 

 twisted awns. The leaves are relatively short, Hat and furrowed 

 on both faces, scabrous with short, obtuse papillae. There is a 

 band of well developed bulliform cells in the furrows between 

 each two mestome bundles on the Upper face of the blade with 

 the outer walls thickened like the other epidermal cells. Stomata 

 occur on both faces and are almost level with the epidermis. The 

 fitereome is very thick-walled and forms a large group below the 



