1887. | BOTANICAL GAZETTE. 233 
slender and hair-like or grass-like, and show little differentiation in the 
parenchyma, which consists usually of very few layers. The epidermis 
generally contains chlorophyll bodies and lacks stomata. The vascular 
nichellia, to a single bundle in which only the sieve-cells can be definitely 
distinguished, or it consists of several well developed bundles coalescent, 
as in Potamogeton nitens. Batween the two extremes there is every 
gradation. In the bundles one or more lysigenous passages occur which 
occupy the position of the large vessels, and at the nodes, where the 
stretching has been too small to destroy them, are fragments of these 
spiral or annular vessels. 
As would be expected, the mechanical elements are but scantily de- 
veloped. Hairs, crystal and tannin reservoirs are rare, while oil-glands, 
latex vessels and resin ducts are always wanting. The root system may 
be entirely suppressed as in Utricularia or fairly developed in more 
amphibious species. 
This series of monographs, by reason of the elaborate work and the | 
elegant illustrations which accompany it, should be in every working 
laboratory in this country. 
Ober die Gerbstoff; und Anthocuan-Behiilter der Fumariaceen und einiger 
anderen Pflanzen. By Dr. W.Z pf, Privat-docent, University of Halle. 
(Bibliotheca botanica, Heft2.) Quarto, pp. 40, 3 double colored plates. 
Cassel: Theodor Fischer. 1886. 
This is the second paper of the same series. The colored plates are 
exquisitely done. We can not do better service to our readers than to 
give a brief abstract of Dr. Zopf's very careful work. 
The relation of the Fumariacez to the Papaveracee suggested to the 
author that he examine them to discover, if possible, the structures cor- 
responding to the latex vessels of the Poppy family. The analogous 
cells, which he designates as idioblasts, occur in all organs in the pri mary 
parenchyma, and also in those tissues which arise in the secondary thick- 
ening of the organs. The primary idioblasts arising from the primary 
meristem are elongated cells (2-10 mm.) without branches; there ondary, 
arising in the cambium of the vascular bundles, are at first of the same 
size as the cambium elements, but afterward elongate. 
ence of light by the formation of organic acids. The yellow ek 
Appears to develop from a culurless chromogen. These pigments have 
