SCIENCE 



A WEEKLY JOURNAL DEVOTED TO THE ADVANCEMENT OF SCIENCE, PUBLISHING THE 



OFFICIAL NOTICES AND PROCEEDINGS OF THE AMERICAN ASSOCIATION 



FOR THE ADVANCEMENT OF SCIENCE. 



Editoeial Committee : S. Nbwcomb, Mathematics ; K. S. Woodward, Mechanics ; E. C. Pickering, 

 Astronomy ; T. C. Mendknhall, Physics ; R. H. Thurston, Engineering ; Ira Remsen, Chemistry ; 

 Charles D. Walcott, Geology ; W. M. Davis, Physiography ; Henry F. Osborn, Paleon- 

 tology ; W. K. Brooks, C. Hart Merriam, Zoology ; S. H. Scudder, Entomology ; C. E. 

 Bessky, N. L. Beitton, Botany ; C. S. Minot, Embryology, Histology ; H. P. Bow- 

 DITCH, Physiology ; J. S. Billings, Hygiene ; William H. Welch, Pathol- 

 ogy ; J. McKeen Cattell, Psychology ; J. W. Powell, Anthropology. 



Friday, March 21, 1902. 



CONTENTS: 



The Distriiutioii of Vacations at American 

 Universities : Professor Charles S. Minot. 441 



The Intellectual Conditions for the Science of 

 Embryology: Professor W. K. Brooks.. 444 



Third Annual Meeting of the Botanists of the 

 Central States: Dr. Albert Schneider.. 454 



Scientific Books: — 



Hazelhurst's Toicers and Tanks for Water 

 Works: F. E. T. Row's Geometric Exer- 

 cises in Paper Folding: Professor P. N. 

 WiLLSON. . Cole and Johnstone's Pleuronec- 

 tes (the Plaice] : Professor C. Jtjtson 

 Herrick 463 



Societies and Academies: — 



Research Oluh of the University of Michi- 

 gan: Professor Frederick C. Newcombe. 

 Zoological Club, University of Chicago : C. 

 M. Child. Biological Society of Washing- 

 ton: F. A. Lucas. New York Academy of 

 Sciences, Section of Geology: Edmund 0. 

 HovET. Section of Biology: Professor 

 Henry E. Crampton. The Boston Society 

 of Natural History : Glover M. Allen ... . 466 



Discussion and Correspondence: — 



The Endoicment of Research: Professor 

 Arthur HoLLiCK. Scientific Nomenclature: 

 Professor Frank W. Very 472 



Engineering Notes: — 



Industrial Economics; Mr. Marconi's 

 Achievement : Professor E. H. Thurston. 473 



Annual Report of the Concilium Bibliographi- 

 cum 475 



Scientific Notes and News 476 



University and Educational News 480 



MSS. intended tor publication and books, etc., intended 

 for review sliould be aent to the responsible editor, Pro- 

 essor J. McKeen Cattell, Garrison-on-Hudson, N. Y. 



THE DISTRIBUTION OF VACATIONS AT 

 AMERICAN UNIVERSITIES. 

 In eonneetion with the work of the com- 

 mittee appointed by the American Asso- 

 ciation for the Advancement of Science 

 for the establishment of Convocation 

 Week, it seemed desirable to gather some 

 more accurate impression as to the periods 

 of vacation now in vogue at our universi- 

 ties and colleges. It is very difficiilt from 

 the reading of catalogues or even by the 

 tabulation of days to gather a clear impres- 

 sion of the differences in the academic 

 calendars of various institutions, so that, 

 almost necessarily, resort was taken to a 

 graphic representation of the facts. The 

 accompanying diagram is perhaps suffi- 

 cient to indicate the main conditions. In 

 this diagram each vertical column repre- 

 sents the calendar year of one institution. 

 The horizontal lines indicate divisions by 

 weeks. The dotted lines indicate the first 

 day of each montli of the academic year 

 from September 1, 1901, to August 31, 

 1902. In each vertical column the black 

 spaces correspond to term time and the 

 white spaces to vacations. As in every 

 case Christmas falls in vacation time, its 

 position is marked by a black line cross- 

 ing each column. Fifteen institutions are 

 represented in the chart; twelve iiniversi- 

 ties and three technological schools. The 

 selection has been made so as to have as 

 representative a variety as possible. 



