August 28, 1913] 



NATURE 



cclxvii 



PETROGRAPHY & PAL/EONTOLOCY. 



New Collections of the Diamantiferous Rocks from the 

 Diamond-fields of South Africa, containing the varieties of 

 KIMBERLITE in their different stale ol weathering. Three different 

 collections of 13, 9 and 6 specimens each. Price inclusive of the corre- 

 sponding thin-sections M. 53-— > 37 —1 -4-— res P- 



New Collection of the typical Rocks of the PRIMARY Platinum 

 Deposits of the Ural Mts., Russia; collected and described by Pro- 

 fessor Dr. Duparc Of Geneva. This very interesting and valuable 

 collection consisis of 13 large size specimens. Price of the collection 

 inclusive of the corresponding thin sections -. M. 120. — 



Beautiful specimens of Alpine Rocks from the collection of Professor 

 Dr. Heim Of Zurich : most instructive for the demonstration of Dynamo- 

 metamorphism. 



New Petrographical Term List NO. 8 sent post free on application. 



Perfect skeletons, beautifully mounted, of UrsUS spelaeuS ; unusually 

 large trunks of Elephas antiquus, several over 3 metres long ; splendid 

 specimens of Mystriosaurus and PlesiosaurUS from Holzmaden ; 

 Cranium of Zeuglodon, Bison priscus, &c. 



New models of Ichthyosaurus with well-preserved skin, showing the 

 whole figure of this reptile; the rare DorygnathuS, model of a most 

 perfectly preserved specimen. 



Collections and single specimens of Minerals, Fossils, Meteorites, bought 

 •and exchanged. 



Dr. F. KRANTZ, 



HHENISH MINERAL OFFICE. BONNON-RMINE, GERMANY. 



ROCK SECTIONS FOR THE MICROSCOPE 



New List of over 600 well cut Rock and Mineral 

 Sections now ready, post free from 



JAMES R. GREGORY <S CO., 



Mineralogists, <5rc. 



139 FULHAM ROAD, SOUTH KENSINGTON, S.W. 



relegrams: "Meteorites, London." Telephone: 2841 Western. 



LIVING SPECIMENS FOR 

 THE MICROSCOPE. 



Volvox, Spirogyra, Desmids, Diatoms, Amceba, Arcella, Actinospharium, 

 Vorticella, Stentor, Hydra, Floscularia, Stephanoceros, Melicerta, and many 

 other specimens of Pond Life. Price is. per Tube, Post Free. Helix 

 pomatia, Astacus, Amphioxus, Rana, Anodon, &c, for Dissection purposes. 



THOMAS BOLTON, 



25 BALSALL HEATH ROAD, BIRMINGHAM. 



MARINE BIOLOGICAL ASSOCIATION 

 OF THE UNITED KINGDOM. 



THE LABORATORY, PLYMOUTH. 



The following animals can always be supplied, either living 

 or preserved by the best methods : — 



Sycon; Clava, Obelia, Sertularia; Actinia, Tealia, Caryopbyllia. Alcy- 

 onium ; Hormiphora (preserved); Leptoplana ; I.ineus, Amphiporns, 

 Nereis, Aphrodite, Arenicola, Lanice, Terebella ; Lepas, Balanus, 

 Gammarus, Ligia Mysis, Nebalia, Carcinus; Patella, Buccinum, Eledone, 

 Pectens Bugula, Crisia, Pedicellina, Holotburia, Asterias, Echinus, 

 Salpa (preserved), Scyllium, Raia, &c, &c. 



For prices and more detailed lists apply to 



Biological Laboratory, Plymouth. THE DIRECTOR. 



WATKINS & DONCASTER. 



Naturalists and Manufacturers of 



CABINETS AND APPARATUS 



FOR COLLECTORS OF INSECTS. BIRDS' EGOS AND SKINS. 

 MINERALS, PLANTS, &c. 

 N.E.— For Excellence and Superiority of Cabinets and Apparatus 

 references are permitted to distinguished patrons, Museums, Colleges, &c 



A LARQH STOCK OF INSECTS, BIRDS' EOUS AND SKINS 



Birds, Mammals, &e., Preserved and Mounted by First-class 



Workmen true to Nature. 

 All Books and Publications (New and Second-hand) on Insects, 



Birds' Eggs, &c, supplied. 



36 STRAND, LONDON, W.C. 



(Five Doors from Charing Cross.) 

 FULL CATALOGUE VOST FREE. 



Sales b\> auction. 



STEVENS' AUCTION ROOMS. Estd. 1760. 



A Sale by Auction is held EVERY FRIDAY 



at 12.30, which affords first-class opportunities for the disposal or 

 purchase of SCIENTIFIC AND ELECTRICAL APPARATUS, 

 Microscopes and Accessories, Surveying Insttuments, Photographic 

 Cameras and Lenses, Lathes and Tools, Cinematographs and Films, 

 and Miscellaneous Properly. 

 Catalogues and terms for selling will be forwarded on application to 

 rvii-. J. G- STEVENS, 

 38 KING STREET, COVENT GARDEN, LONDON, W.C. 



THE 



• SIRIU S' 



X-EtA-V 



TUBE, 



Price 15/- 



Sole Maker. 



H. HELM, 



66 Hatton Carden, 



London. 



ACTUAL MAKER 



of all kinds of 



LIST FREE. 



MINERAL S, ROCKS, FOSSILS, A PPARATUS, 

 WIRELESS DETECTORS, AND MINERALS. 



KINDLY NOTE REMOVAL OF 



RUSSELL & SHAW, 



MINERALOGISTS. 



IX John Street, Theobald's Road, 

 — TO — 



38 GT. JAMES STREET, BEDFORD ROW, 



LONDON, W.C, 



Third door (left side) from Theobald's Road. 



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