tgor | CURRENT LITERATURE 429 
apples, by J. C. ARTHUR ; Additions to the flora of Indiana, and Some mid- 
summer plants of southeastern Tennessee, by STANLEY COULTER; A bac- 
terial disease of tomatoes, by WILLIAM STUART; Description of certain 
bacteria obtained from nodules of various leguminous plants, by SEVERANCE 
BURRAGE; Mycological notes from Wells and Whitley counties, by E. B 
WILLIAMSON.— J. M. C 
NOTES FOR: STUDENTS. 
Jost* has published an interesting and valuable summary of the recent 
contributions to our knowledge of the synthesis of proteids. Recent workers 
generally agree, in contrast with the older view of Schimper, that proteid 
synthesis can take place in the dark and in tissues without chlorophyll, pro- 
vided carbohydrates are at hand.— H. C. Cowes. 
F. E. Weiss,’ after examining a very large number of specimens of 
Lepidophloios and Lepidodendron, has concluded that the arrangement of 
the cells making up the phloem region, at least as seen in transverse section, 
not only does not preclude them from being of the nature of true phloem ele- 
ments, but makes it very probable that the function of this tissue was that of 
a normal phloem.—J. M. C. 
BENJAMIN D. GILBERT® has published a useful list of North American 
pteridophytes. According to the editor, the four objects in view were (1) to 
present a convenient alphabetical list ; (2) to make a list as comprehensive as 
Possible in including all published forms; (3) to have a complete list which 
uses a Conservative nomenclature; and (4) to seabieg the list of varieties of 
Athyrium filix-foemina which the author has found.—J. M. C. 
J. W. HaRSHBERGER® has been investigating the limits of variation in 
certain plants by the statistical method, largely as a contribution to the prob- 
lem of species. Variations in size and shape of leaves, in weight and volume 
of fruit, and in number of seeds were tabulated. In Liriodendron, Tulipifera, 
Sanguinaria Canadensis, and Ailanthus glandulosa it was found that varia- 
tion in size and form is due in part to the persistence of juvenile forms.— 
THE GRASSES OF Iowa” is the title of a volume prepared by Professors 
_* Biol. Cent. 20 : 625-637. 1900. 
7On the pom of rs an alae and Lepidodendron. Manchester Memoirs 
45 :no. 7. pls. 2-3. 
® Working list an ese American pteridophytes (north of Mexico), gor a with 
descriptions of a number of varieties not heretofore published. Utica, N. Y.: Pub 
lished for the Editor. IgoI 
* The limits of variation in plants. Proc. Philad. Acad. 53 : 303-319. 1901. 
Towa Geological Survey. Bulletin No. 1. pp. 525, with 220 illustrations. I90I. 
