IV THE NAUTILUS. 



THE MANUAL OF CONCHOLOQY. 



Founded by the late Geo. W. Tryou, Jr., continued under the care of the Con- 

 chological Section, Academy- of Natural Sciences of Philadelphia, by Henry A 

 Pilsbry, Conservator. 



The Manual of Conchology is a. fully illustrated monography of recent mollusks. 



Issued in octavo form, in quarterly parts. Each part comprises 64 (or more) 

 pages of letterpress, and 15 to 20 plates. 



Two series are now in progress : the FIRST SERIES, Marine Univalves, of which 

 fifteen volumes have appeared, finishing the series as planned by its illustrious 

 founder. A supplemental volume to this series will be issued this year, to contain 

 some families not heretofore considered. Of the SF.COXD SERIES, Terrestria 1 

 Molluscs, Nine Volumes have been published, completing Helix with index. A few 

 copies of Vol. IX of this series, " Guide to the Study of Helices " will be sold separ- 

 ately at the regular subscription price. Separate copies of the Index, suitable for 

 the purposes of a Catalogue or Check list can also be had at $1.00 each. 



The Mouography of the Bulimi\\^ been commenced in the tenth volume. 



The illustrations of the Manual have received high commendation, and are fully 

 equal to the best figures of shells published. 



Prices : Plain (uncolored) edition 53.00 per part. Colored edition $5.00 per part. 

 Fine edition (both colored and India-tinted plates) SS.oo per part. 



Structural and Systematic Conchology. by GEO W. TKYOX, Jr. 



A COMPLETE CONCHOLOGICAL TEXT BOOK of 1200 pages, 140 plates and over 3500 

 figures of Genera, Anatomy, etc. Three volumes bound in one. Cloth. Price $6.00. 



For further information or descriptive circular, with sample plates of Manual, 

 address : 



S. RAYMOND ROBERTS, Treasurer, 



P. 0. Address, GLEN RIDGE, NEW JERSEY, U. S. A. 



American Naturalist" 



MANAGING EDITORS : 



PROFS. E. D. COPE, Philadelphia, Pa., and J. S. K1NGSLEY, Boston, Mass. 



ASSOCIATE EDITORS: 



DR. C. O. WHITMAN, of Chicago University, Chicago, III. 



DR. C. E. BESSEY, of The University of Nebraska, Lincoln, Neb. 



DR. H. C. MERCER, of The University of Pennsylvania. 



PROF. C M. WEED, College of N. H., Hanover, N. H. 



PROF. W S BAYLEY, of Colby University, Watervilie Me 



P!-.OF. E A. ANDREWS, of Johns Hopkins University, Baltimore, Md. 



PROF. A. C. GILL, Cornell University, Ithaca X V 



PROF. H. C. WARREN. Princeton University, Princeton, N J. 



ERWIN !'. SMITH, Department of Agriculture, Washington, D. C. 



SAMI>LE COF-Y, IS CENTS. 

 THE EDWARDS &, DOCKER CO., 



518-530 MINOR ST. I 1 1 I I \ I > I I I 1 1 I I | . N. A. 



'THE MUSEUM' 



A new Journal published on the 15th of each month by Walter 

 F. Webb, Albioil, N. Y., devoted to NATUKAL SCIENCE, will 

 contain, from time to time, fine bargains in shells and interesting 

 articles in this line. SEND lOcTs. FOR COPY AND MY CATALOGUE. 



