158 BOTANICAL GAZETTE [Aucust 
He does not refer to the work of KRAEMER?3 or of MAQUENNE and Rovx,?4 who 
independently and from very different standpoints have found evidence of such 
a mixture. Since starch shows seven characteristic colloidal properties and 
only two crystalline properties he concludes that it is a colloid. 
The author discusses at length the theories of staining with anilin colors, 
dismisses as wrong the adsorption theory, and concludes that, while in some 
cases, as in the staining of proteids, the reaction may be largely chemical, in most 
cases the taking up of the color is by solution, dyes not soluble in water being: 
soluble in starch. He further concludes that the solution is a liquid and not a 
solid solution, the colloidal starch in the swollen grains being in a liquid state.— 
Heterospory in Sphenophyllum.—This genus has been regarded as strictly 
homosporous, but THopAy?5 now describes and figures a section through the 
strobilus of 5. Dawsoni which shows two adjacent sporangia, one of them con- 
taining spores of uniform size, the other containing fewer and larger spores, 
among which are seen numerous very small aborted ones. These contrasting 
sporangia certainly suggest heterospory, but the largest of the supposed mega- 
spores has only about 1.5 times the diameter of the spores of the other sporan- 
gium. It will be remembered that in Calamostachys Casheana the megaspores 
are only three times as large as the microspores, and this was felt to be a remark 
ably small difference.—J. M. C. 
Proteid metabolism in the ripening barley grain.—The first section of a papet 
to consist of three has been presented by ScCHJERNING.?° A short notice to call 
the attention of physiologists is appropriate here, but the reliability of the methods 
and conclusions must remain unconsidered. The author finds that spectes, 
variety, or type per se do not affect the chemical composition of the dry matter of 
the grain so far as the nitrogenous and mineral constituents are concerned. 
the grain develops to maturity there is a constant tendency toward equilibrium 
between the nitrogenous constituents, which is established at maturity and which 
is not disturbed during subsequent storage except in the case of certain albu- 
mins.—RAYMOND H. Ponp. 
23 KRAEMER, HENRY, The structure of the starch grain. Bot. GAZETTE. 34: 
341. 1902. : 
24 MAQUENNE et Rovx, Sur la constitution, la saccharification et la rétrograd 
ation des empois de fécule. Comptes Rendus Acad. Sci. Paris 140: 130371308. cai 
2s THopay, D., On a suggestion of heterospory in Sphenoph yllum Dawson 
New Phytol. §:91-93. figs. 14. 1906. 
26 SCHJERNING, H., On the protein substances of barley, in the grain itself and 
during the brewing processes: First section: On the formation and transformation 
of protein substances during the growth, ripening, and storage of barley. Compt- 
Rend. Lab. Carlsberg 6: 229-305. 1906 
