84 Scientific Intelligence. 



Jena, 1911 (Gustav Fischer). — Cytologists have hoped that the 

 study of the nuclei of unicellular animals and plants would throw 

 light on the complex morphology of the nuclear apparatus of 

 higher forms, and on cell problems in general. In this they have 

 not been disappointed, though continued research has shown 

 that the structure of the cell of the lower organisms is far more 

 specialized and complicated than was anticipated, and thus it 

 offers an immense problem in itself. Professor Hartmann in this 

 paper makes a critical analysis of some of the chief types of nu- 

 clear phenomena of the protista in an endeavor to derive some 

 general principles from the mass of recently accumulated data. 

 The result is suggestive, especially to one who has followed the 

 recent advances in protisten cytology. l. l. 'w. 



13. Elements of Descriptive Geometry ; by Albert E. Church 

 and George M. Bartlett. Pp. 286 with 143 figures. New 

 York (American Book Company). — A modern treatment of 

 descriptive geometry, with applications to spherical projections, 

 shades and shadows, perspective, and isometric projections, for 

 the use of technical schools and colleges. It is a thorough revision 

 of Professor Church's book which has been long in use. The 

 figures and text are included in the same volume, each figure 

 being placed beside the corresponding text. In the treatment of 

 curved surfaces, all problems relating to single curved surfaces 

 are taken up first, then those of warped surfaces, and lastly those 

 of surfaces of revolution. Thus the procedure is from the simple 

 to the complex. An abundance of practical exercises is provided. 



w. E. 



14. Power ; by C. E. Lucke. Pp. 316; 223 figures. New 

 York, 1911 (The Columbia University Press). — This book is com- 

 posed of eight popular lectures which emphasize the importance, 

 in the organization of society, of the substitution of mechanical 

 power for hand and animal labor. It is liberally illustrated by 

 cuts of machinery and plants for the conversion of natural energy 

 in any of its available forms into useful work, and in an interest- 

 ing manner discusses the physical principles involved, d. a. k. 



Obituary. 



Professor Nevil Story - Maskelyne, the veteran English 

 mineralogist professor at Oxford from 1856 to 1895 and long in 

 charge of the mineral collection of the British Museum, died on 

 May 20 at the age of 8*7 years. 



Dr. A. E. Tornebohm, the well-known Swedish geologist, died 

 early in June at the age of 72 years. 



Professor C. G. Pringle, curator of the Herbarium at the 

 University of Vermont, died at Burlington on May 25 at the age 

 of 73 years. 



William R. Dudley, Professor of Botany at Stanford Uni- 

 versity, died on June 4 at the age of 64 years. 



Mrs. Williamina Paton Fleming, curator of astronomical 

 photographs at the Harvard College Observatory, and discoverer 

 of many new stars and nebulae, died on May 21 at the age of 

 54 years. 



