﻿1903] CURRENT LITERATURE 65 



Kraemer,=° in his study of the structure of the starch grain and the cell- 

 wall, has discovered that certain appearances described by various authors 

 as indicating a continuity of protoplasm are due to a peculiarity in the struc- 

 ture of the cell-wall, which is made manifest by the reagents employed, and 

 which resembles the structure of the starch grain. He also calls attention to 

 the fact that investigators have generally fallen into the error of supposing 

 that a certain aniline dye could be regarded as a differential stain for proto- 

 plasm, whereas the fact is that many colloidal carbohydrates, as mucilage and 

 pectin, and oils and other substances as well, take up these stains. If the sub- 

 stance in the cell-wall which takes up the stain is protoplasm, what is it in 

 the starch grain ? — J. M, C. 



Storer^^ adds very materially to our knowledge of mannan as a stored 

 food-stuff in plants by a series of notes on the detection of its hydrolysis 

 product, mannose, A long experience in the study of these substances gives 

 him the right to speak authoritatively on the methods best adapted to their 

 identification and estimation. The methods are clearly described and the 

 difficulties fully discussed. He finds abundance of mannan in the following 

 plant tissues : date stones, ivory nut, flesh of ripe cocoanut, seeds of Trifolium 

 repens, and the wood of Pitius Strobus, P. rigida, Picea excelsa, Larix 

 leptolepis^ Tsuga canadensis, Jtmipertis virginiana, and Chatnaecy parts 

 sphaeroidea. Smaller amounts of mannan are contained in a number of 



other tissues tested. — Burton E. Livingston, 



Underwood ^= has given a surprising account of the genus Gymno- 

 gramme as presented in Hooker's Synopsis Filicum. So far from being a 

 natural assemblage, it contains among its species a number of generic groups, 

 several of which bear no close phylogenetic relations to the others or to each 

 other, some even belonging to different tribes. Some of these genera sub- 

 merged under Gymnogramme are related to the Polypodieae, others to the 

 Aspidieae, one possibly to the Vittarieae, but more are distinctly related to 

 the Asplenieae. The name Gymnogramme being a typonym of the mono- 

 typic Gymnopteris, established thirteen years earlier, disappears from botani- 

 cal nomenclature. The two species occurring within the limits of the United 

 States heretofore referred to Gymnogramme represent two distinct genera, 

 CeropterislAVi^ and Bommeria Fourn,— J. M. C. 



Mendel =3 has investigated the products formed by the action of papain, 

 the proteolytic enzyme of the fruit of Carica papaya, upon proteids, with the 



=^Kraemer, Henry, On the continuity of protoplasm. Proc. Amer. Phil. Soc. 



41: 174-180, pls.2I~23, 1902. 



"Storer, F. H., Testing for mannose. Bull. Bussey Inst, 3 : 13-45- ^902. 



=' Underwood, L. M., American ferns. IV. The genus Gymnogramme of the 

 Synopsis Filicum. Bull. Tor. Bot. Club 29 : 617-634. IQ02. 



*3 Mendel, L. B., Observations on vegetable proteolytic enzj-mes, with special 

 reference to papain. Am. Jour. Med. Sci. pp. 9. (Aug.) 1902. 



