602 Angewandte Botanik 



Ophiopogon, various Gramineae, for instance Uniola etc. The sub- 

 terranean stem is densely covered with glandulär hairs. In regard 

 to the leaves, these are flat, glabrous, and approximately dorsiven- 

 tral with stomata distributed over both faces, and with the chloren- 

 chyma differentiated into a ventral palisade-tissue and a dorsal 

 pneumatic of several layers of irregularly branched cells. Around 

 the veins the chlorenchyma becomes more compact showing an 

 almost radiate arrangement around these; all the mestome-strands 

 are coUateral, but show the same peculiarity as those of the stem, 

 by the leptome being divided by Strands of sterome. Theo Holm. 



Holm, T., Medicinal plants of North America. 37. Agropyrum 

 yepens{l..)B ediViY. (Merck's Report. 19. p. 65—68. fig. 1 — 12. March 1910.) 



Agropyrum repens is one of the few Gramineae which is official, 

 and the drug Triticum is yielded by this species, represented by 

 the rhizome, gathered in the spring, it is known, also, as „Radix 

 Graminis'\ and as „Rhisotna Graminis'\ It contains about 50/^ tri- 

 ticin, which according to Hager may be identical with irisin and 

 graminin; furthermore inosit, sugar (probably levulose), and mannit, 

 Triticum is ,used for its influence upon the genito-urinar}^ organs, 

 in irritable bladder, and in cystitis. The plant is described and 

 figured, and from the anatomical examination the foUowing points 

 are of interest. The root has a heterogeneous cortex, the peripheral 

 strata being thinwalled, the innermost considerably thickened; endo- 

 dermis is, also, thickwalled, and the pericambium consists of two 

 layers outside the proto-hadrome, but of only one outside the 

 leptome. In none of the roots examined was the pericambium inter- 

 rupted by the proto-hadrome, while Klinge enumerates this species 

 as an exaraple of roots with the proto-hadrome-vessels bordering on 

 endodermis. Characteristic of the rhizome is the very regulär dispo- 

 sition of the mestome-strands, there being one band in the cortex, 

 and another (concentric with these) inside the stereomatic pericycle; 

 all the mestome-strands are collateral, and endodermis is very 

 distinct. The culm has no endodermis, but a closed sheath of 

 stereome surrounding two concentric bands of mestome-bundles, 

 all of which are collateral. The leaves have stomata on both faces, 

 and the chlorenchyma consists throughout of roundish cells, no 

 palisades being developed. A thinwalled parenchyma-sheath and a 

 moderately thickened mestome-sheath Surround the veins, but other- 

 wise the structure is not different from that which has been described 

 as the most frequently met with in this family, the Gramineae. 



Theo Holm. 



Holm, T., Medicinal plants ot North America. 38. Rhus 

 Toxicodendron L. (Merck's Report. 19. p. 95—98. fig. 1—14. April 

 1910.) 



Formerly the fresh leaves of this plants were ofificial in the 

 U. S. Pharmacopoeia, yielding „Extractum Toxicodendri" and 

 „Tinctura Toxicodendri". A peculiar non-volatile oil resides in 

 all parts of the plant, by Pfaff called „toxicodendrol". Applied to the 

 skin this oil causes eruptions, while the so-called „toxicodendric acid" 

 seems to be non-toxic. All the organs of the plant contain a latex, 

 which soon becomes black on exposure to the air, leaving upon 

 linen a stain that cannot afterward be removed, hence this latex 



