(ii) PEEFACE. 



with this is a list of tlie principal serial works from which 

 extracts or quotations are to be fonnd in the volume. 



Fifth, an extremely minnte alphabetical index of authors 

 and subjects. 



Sixthj a systematic and analytical table of contents, by 

 means of which reference can readily be made to whatever 

 the volume contains, bearing upon any particular line of 

 inquiry. 



Seventh, in compliance with a generally expressed wish, 

 the names of the authors of the different portions of the 

 Scientific Summary are given for the first time in the 

 present volume of the Hecord, in connection with their 

 respective communications, all of them men occupjdng the 

 front rank in America as authors and investigators. Other 

 collaborators not contributors to the first division of the 

 volume are Professor C. F. Ilimes, of Dickinson College, 

 Carlisle, Pa. ; Professor F. W. Clarke, of the University of 

 Cincinnati; Professor E.D. Cope, of Philadelphia; Profess- 

 or F.Y. Ilayden; Major J.W. Powell; Lieutenant George 

 M.Wheeler, U. S. A., and several others who prefer to re- 

 main un mentioned. 



It will be readily understood that the present volume 

 is prepared for the general public, who desire to become 

 acquainted with the more prominent steps of advancement 

 during the year, without the trouble of resorting to the 

 sources of original information concerning the same. 

 Specialists may find little or nothing in it to merit their 

 attention, and, indeed, they may naturally be inclined to 

 criticise the work for not being more complete. It must 

 be borne in mind, however, that the work is limited in 

 extent, and that, in view of the enormous subdivision of 

 labor at present in the line of scientific investigation, any 

 attempt at exhaustiveness w^ould involve a vast increase in 

 the size of the book. At the present time there is scarcely 

 a branch of science which is without one or more journals 

 as its organs and an annual record devoted exclusively to 

 its history; and to these reference should be made for 

 more minute information. It is hoped, however, that but 

 little of general or popular interest has been overlooked. 



