BECKER BROTHERS, 



No. 6 Murray Street, New York, 



Manufacturers of Balances and Weights of Precision for Chem- 

 ists, Assayers, Jewelers, Druggists, and in general for every use 

 where accuracy is required. 

 April, 18*71. — [tf.] 



^"CTZBXjIC-A-TIOnsrS OIF THE 



JOHNS HOPKINS UNIVERSITY. 



I. American Journal of Mathematics. S. Newcomb, Editor, and T. Craig, 



Associate Editor. Quarterly. 4to. Volume X in progress. $5 per 

 volume. 



II. American Chemical Journal. — I. Bemsen, Editor. Bi-monthly. 8vo. 



Volume IX in progress. $3 per volume. 



III. American Journal of Philology. — B. L. Gtldersleeve, Editor. Quar- 



terly. 8vo. Volume IX in progress. $3 per volume. 



IV. Studies from the Biological Laboratory. — Including the Chesapeake 



Zoological Laboratory. H. N. Martin, Editor, and W. K. Brooks, Asso- 

 ciate Editor. 8vo. Volume IV in progress. $5 per volume. 



V. Studies in Historical and Political Science. — H. B. Adams, Editor. 



Monthly. 8vo. Volume VI ready. $3 per volume. 



VI. Johns Hopkins University Circulars. — Containing reports of scientific 



and literary work in progress in Baltimore. 4to. Vol. VII in progress. 

 $1 per year. 



VII. Annual Report. — Presented to the President by the Board of Trustees, 

 reviewing the operations of the University during the past academic year. 



VII. Annual Register. — Giving the list of officers and students, and stating 

 the regulations, etc., of the University. Published at the close of the Aca- 

 demic year. 



ZOOLOGY AND PALEONTOLOGY. 



LARGE STOCK IN RECENT 



VERTEBRATES AND EVERTEBRATES. 



We arrange and furnish complete collections for educational pur- 

 poses, demonstrations and exhibitions in any or all departments of 

 Zoology. 



Collections of recent shells also for the study of Paleontology. Col- 

 lection of skeletons and skulls for the study of Osteology. Large stock in 



FOSSILS, 



(especially of the Tertiary Period). 



From the Mayence basin we have remains of Elephas, Mastodon, 

 Dinotherium, Hippotherium, Palaeomeryx, Aceratherium, Halitherium, 

 etc. Besides, we sell fragmentary scales of 



G-LYPTODON CLAVIPES, 



complete specim ns of Ichthyosaurus and many other interesting 

 Fossils. On demand we furnish catalogues and lists. 



"Linnaea" Institute for Natural History, Berlin, N. W. 6, Ger- 

 many. Our Agent in the U. S. A., 



HERMANN ROLLE, 



No. 33, Avenue A, New York City. 



