BOTANY. 643 



"Stated briefly, the following conclusions regarding the arsenic content of papers 

 and fabrics sold on the American market may be drawn from the data collected: 



" (1) If 0. 1 grain per square yard is considered as the maximum amount of arsenic 

 allowable in wall papers, the condition of the market is quite satisfactory, but if for 

 reasons previously mentioned the limit is reduced to 0.05 grain per square yard some 

 improvement should be made. 



" (2) The arsenic content of glazed, shelf, and crepe papers is as small as could be 

 reasonably expected. 



" (3) Entirely too large a percentage of the dress goods, dress furs, and fur rugs 

 sold on the American market contain excessive amounts of arsenic. 



" (4) The presence of excessive amounts of arsenic in such goods as are described 

 in paragraph 3 is dangerous to the health of a large number of people, especially 

 those who are susceptible to arsenic poisoning. 



" (5) The arsenic content of miscellaneous fabrics other than dress goods — such as 

 pillow covers, hangings, carpets, etc. — is in the main satisfactory with the present 

 limit for arsenic; but if this limit were reduced to 0.05 grains per square yard, as 

 advocated for wall papers, a considerable number of carpets would be without the 

 pale. ' ' 



The abstracting of current chemical literature, H. Marshall ( Chem. Xe/rs, 90 

 {1904), No. 2350, pp. 283, 284). — The auth' 1 calls attention to the multiplication of 

 abstracts, and outlines a plan requiring international cooperation by which this will 

 be avoided. It is suggested that all abstracts be prepared under (lie direction of an 

 international commission and also translated into the different languages under the 

 same supervision. The publication of the various editions would devolve upon the 

 separate organizations. It is considered that the initiation of the international 

 scheme for physico-chemical papers shows that the difficulties in the way of the 

 scheme proposed are not insuperable. 



BOTANY. 



Plant morphology, O. W. Caldwell (New York: Henry Holt & Co., 1904, pp. 

 VI-\-190). — This is a revised and rewritten edition of the Handbook of Plant Dis- 

 section, by J. C. Arthur, C. R. Barnes, and J. M. Coulter, issued in 1886. Since 

 that time the methods of laboratory work and plant morphology in general have 

 made such advances as to require a rewriting of the book. 



The influence of dry and moist air on the form and structure of plants, P. 

 Eberhard (Ann. Set. Nat., Bot., 18 (1903), pp. 61-152, pi. l,figs. 17; rev. in Gard. 

 Clmm., 3. ser., 36 (1904), No. 915, p. 17). — The author has investigated the effect of 

 excessive drought and a saturated soil and atmosphere on the form and structure of 

 a large number of species of plants. As a result of his investigations he concludes 

 that excessive drought results in a dwarfing of the stems, associated with an increased 

 rigidity, and diminished length, but an increase in the number of internodes. There 

 is also a reduction in the size of the leaves, an increase in their thickness and inten- 

 sity of color, an increase in hairiness, and an earlier leaf fall. 



The effect produced by extreme drought on the internal anatomy of the plants was 

 shown in a smaller size of the epidermal cells; a reduction of the cortex and pith; an 

 increase of secretory canals and their secretions, as well as of raphids; an increase of 

 sclerenchyma, collenchyma, and wood; a hastening of development of the bark; and 

 an increase in the thickness of cell walls and in the activity of the generative cells. 

 Under a moist atmosphere precisely the converse took place. 



The adaptation of plants to the intensity of light, .1. Wiesner (Compt. Rend. 

 Acad. Sci. [Paris], 138 (1904), No. 22, pp. 1346, 1347).— -The author has for a number 

 of years been conducting experiments on the effect of intensity of light on plants, 

 pursuing his studies in different parts of the world from 6° to 79° north latitude and 



