October 13, 1916] 



SCIENCE 



543 



be led to the conclusion that there is some 

 radical distinction between plants and ani- 

 mals in these respects. 



Many matters of importance are treated in 

 the book, especially the vexed question of the 

 nature of " mutations," to which no justice 

 can be done here. All that can be now at- 

 tempted is an outline of the essential discov- 

 eries. To some it may seem that the disposi- 

 tion of this article is towards undue scepti- 

 cism. To doubt the theory of cross-overs, for 

 instance, at this date is almost in effect to 

 " draw an indictment against a nation," which 

 we know on high authority is an impossible 

 task. Let it then be explicitly said that not 

 even the most sceptical of readers can go 

 through the Drosophila work unmoved by a 

 sense of admiration for the zeal and pene- 

 tration with which it has been conducted, and 

 for the great extension of genetic knowledge 

 to which it has led — greater far than has been 

 made in any one line of work since Mendel's 

 own experiments. 



W. Bateson 



PROCEEDINGS OF THE NATIONAL 

 ACADEMY OF SCIENCES 



The ninth number of Volume 2 of the Pro- 

 ceedings of the National Academy of Sciences 

 contains the following articles : 



The Mechanism of Diffusion of Electrolytes 

 through Animal Membranes: Jacques Loeb, 

 Eockefeller Institute for Medical Eesearch, 

 New York. For the diffusion of certain elec- 

 trolytes through animal membranes there is 

 required besides the osmotic pressure a sec- 

 ond effect called the " salt effect " upon the 

 membrane. This consists probably in an ioni- 

 zation of the protein molecules of the mem- 

 brane. 



The Rotation and Radial Velocity of the 

 Spiral Nebula N.G.C. k59k'- Francis G. Pease, 

 Mount Wilson Observatory, Carnegie Insti- 

 tution of Washington. The radial velocity is 

 + 1,180 km., in good agreement with the value 

 found by Slipher. The linear velocity of 

 rotation at a point 2 minutes of arc from the 

 nucleus is over 330 km. 



A Simple Method for Determining the Colors 



of the Stars: Frederick H. Seares, Mount 

 Wilson Solar Observatory, Carnegie Institu- 

 tion of Washington. The method suggested 

 consists in determining the ratio of exposure- 

 times which is necessary to produce photo- 

 graphic and photovisual or more briefly, blue 

 and yellow, images of the same size. 



Studies of Magnitudes in Star Clusters, 

 III. The Colors of the Brighter Stars in Four 

 Globular Systems: Harlow Shapley, Mount 

 Wilson Solar Observatory, Carnegie Institu- 

 tion of Washington. It is concluded that in 

 all the clusters examined and probably in all 

 globular clusters the volumes of the bright red 

 stars are very great in comparison with the 

 stars that are fainter and relatively blue. 



The Effect of an Electric Field on the Lines 

 of Lithium and Calcium: Janet T. Howell, 

 Mount Wilson Solar Observatory, Carnegie 

 Institution of Washington. Lithium and 

 calcium were examined both for longitudinal 

 and transverse effects. 



A Proof of White's Porism: A. B. Coble. 



A Contribution to the Petrography of the 

 Philippine Islands: J. P. Iddings and E. W. 

 Morley, Brinklow, Maryland and West Hart- 

 ford, Conn. Six detailed analyses are given of 

 rocks from Luzon, P. I. 



Salt Antagonism in Gelatine: W. O. Fenn, 

 Laboratory of Plant Physiology, Harvard Uni- 

 versity. The experiments on gelatine sup- 

 port the hypothesis that anions antagonize 

 cations in their effects upon organisms. The 

 hypothesis here developed resembles that of 

 Clowes except that it requires that NaCl 

 should antagonize any electrolyte which has 

 either a strong anion or a strong cation. The 

 point of maximum antagonism is an isoelec- 

 tric point at which the amount of alcohol 

 needed for precipitation is at a minimum, and 

 the aggregation or amount of precipitation is 

 at a maximum. 



Similarity in the Behavior of Protoplasm 

 and Gelatine: W. 0. Fenn, Laboratory of 

 Plant Physiology, Harvard University. A 

 close analogy to Osterhout's experiments on 

 the electrical resistance of Laminaria is found 

 in gelatine (plus NaOH), if we assume that 

 the effect of time in the Laminaria experi- 



