gto] CURRENT LITERATURE 319 
Oxidase of Medicago.—EvLerR and Bo.rin?? claim to have succeeded in 
the protein bodies were thrown down, and by treatment with animal charcoal, the 
dextrin-like substances withdrawn. They concluded that this pure laccase con- 
sists of mono-, di-, and tribasic aliphatic oxy-acids. ‘The presence of the citrate, 
malate, and mesoxalate of this base was certainly established, and it is almost 
certain that the glycolate is a fourth salt. 
They have already3° shown that various salts of this type will produce oxida- 
tions qualitatively and quantitatively, similar to those produced by the laccase of 
Medi hey now extend these tests to the new salts found, and to mixtures 
of the salts, and find marked agreement between the oxidations produced by them 
and those produced by laccase.—WILLIAM CROCKER. 
Origin of the cell wall.—In an extended paper on vegetative cell division in 
the higher plants, Postrma3t pays particular attention to the origin and develop- 
ment of the cell wall. Half of the paper consists of an excellent presentation and 
discussion of the literature, while the writer’s own researches deal with the stomata 
of Aneimia fraxinijolia, root tips of Allium Cepa, and stem tips of Psilotum tri- 
quetrum. In case of the peculiar, isolated stomata of Aneimia, the cell wall is 
formed as in other vegetative cells, and consequently the problem i in the three 
forms is much the same. While the writer finds that the cell wall arises in greater 
or less connection with the spindle, the material of the spindle is not believed to 
furnish all the material for the beginning of the wall. A mother Hautschicht 
Splitting into two daughter Hautschichts, as sometimes described, could not be 
found. A single plate with rather small figures is hardly sufficient to illustrate 
so difficult and so important a problem.—CHARLES J. CHAMBERLAIN. 
of monocotyledons.—Evans3* has undertaken a somewhat exten- 
Sive study of monocotyledonous seedlings and also of the mature embryos. Not 
only has the structure at various stages been investigated, but also the effect of 
deep and shallow seed-sowing. The present paper is a record of some of the 
results, chiefly those in reference to the “plumular meristem”; and a final paper 
will review all the facts and suggest the conclusions. The facts are to be used, 
in part, in connection with the question as to the origin of the lateral position of 
en 
ULER, H., AND Boxin, Ivan, Ueber die Reindarstellung und die chemische 
Bicencs, einer Oxydase. Arkiv for Kemi, Mineralogi, och Geologi 3:000, 1909. 
i » Zeit. Physiol. Chem. 51:80. 1908. ; 
3t Posta, G., Bigdrage tot de Kennis van de a. celdeling bij de hogere 
— omen pp. 117. pl. r. Groningen: M. d 
Ss, W. Epcar, On the further development Sa germination of mono- 
cotylous hci: with special reference to their plumular meristem. Notes Roy. 
Bot. Gard. Edinburg No. 2i:1-21. pls. 53, 54. Jigs. 8. 1909. 
