2 eS ae  ———— 
NOVEMBER 20, 1913] 
MINERALOGY —CRYSTALLOGRAPHY— 
PETROGRAPHY—GEOLOGY. 
Ask for our new 
CATALOGUE XVIII. 
(2nd Edition) 
for the use of Middle and High Schools and Universities. 
Part I, 260 pages, 110 Illustrations. 
This catalogue has been prepwed with the view of making an exhaustive 
compilation of all educational appliances for the teaching 
of Mineralogy and Geology [from a scientific as well as from 
a practical pv-int of view. All the subjects are treated typically, and 
instructive specimens have been selected with the greatest care. A close 
examination of the catalogue will show, that owing to its careful compo- 
Sition it gives the opportunity of procuring the most complete outfit for the 
various schools for instruction in and the study of the subjects named, 
Catalogue No. 18, Part I, will be sent free on application. 
Part II will appear within the course of the year. 
(Collections and single specimens of Minerals and Fossils, 
Meteorites bought and exchanged.) 
Dr. F. KRANTZ, 
RHENISH MINERAL OFFICE, BONN-ON-RHINE, GERMANY. 
Established 1833. Established 1833. 
ROCK SECTIONS FOR THE MICROSCOPE 
New List of over 600 well cut Rock and Mineral 
Sections now ready, post free from 
JAMES R. GREGORY & CO., 
Mineralogists, Gc., 
139 FULHAM ROAD, SOUTH KENSINGTON, S.W. 
Telephone : 2841 Western. 
GENERAL 
Telegrams: ‘‘ Meteorites, London.” 
LIVING SPECIMENS FOR 
THE MICROSCOPE. 
Volvox, Spirogyra, Desmids, Diatoms, Amceba, Arcella, Actinosphzrium, 
Vorticella, Stentor, Hydra, Floscularia, Stephanoceros, Melicerta, and many 
other specimens of Pond Life, Price 1s. 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 bejsupplied, either living 
or preserved by the best methods :— 
Sycon ; Clava, Obelia, Sertularia; Actinia, Tealia, Caryopbyllia, Alcy- 
onium; Hormiphora (preserved); Leptoplana; Lineus, Amphiporus, 
Nereis, Aphrodite, Arenicola, Lanice, Terebella; Lepas, Balanus, 
Gammarus, Ligia Mysis, Nebalia, Carcinus; Patella, Buccinum, Eledone, 
Pectens Bugula, Crisia, Pedicellina, Holothuria, Asterias, Echinus, 
Salpa (preserved), Scyllium, Raia, &c., &c. 
‘or prices and more detailed lists apply to 
_ Biological Laboratory, Plymouth. 
THE DIRECTOR 
NATURE 
CXXV 
WATKINS & DONCASTER, 
Naturalists and Manufacturers of 
FUR COLLECTORS OF INSECTS, BIRDS' EGGS AND SKINS. 
MINERALS, PLANTS, &c. 
N.B.—For Excellence and Superiority of Cabinets and Apparatus, 
references are permitted to distinguished patrons, Museums, Colleges, &c. 
A LARGE STOCK OF INSECTS, BIRDS’ EGGS AND SKINS. 
SPECIALITY.—Objects for Nature Study, 
Drawing Classes, &c. 
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. 
86 STRAND, LONDON, W.C. 
(Five Doors from Charing Cross.) 
FULL OATALOGUE POST FREE. 
Sales by Euction. 
STEVENS’ AUCTION ROOMS.  Estp. 1760. 
A Sale by Auction is held EVERY FRIDAY 
at 12.30, which affords first-class opportunities for the disposal or 
racrcioas of SCIENTIFIC AND ELECTRICAL APPARATUS, 
Microscopes and Accessories, Surveying Instruments, Photographic 
Cameras and Lenses, Lathes and Tools, Cinematographs and Films, 
and Miscellaneous Property. see 
Catalogues and terms for selling will be forwarded on application to 
Mr. J. Cc. STEVENS, 
38 KING STREET, COVENT GARDEN, LONDON, W.C. 
X-RAY TUBE, 
Price 15/- 
Sole Maker, 
H. HELM, 
66 Hatton Carden, 
_London. 
ACTUAL MAKER 
of all kinds of 
X-Ray and Vacuum 
Tubes, &c, 
LIST FREE, 
WEINE RATLS. 
Now on view, some choice specimens of 
DATOLITE 
from Parc Bean Cove, Mullion, Cornwall. Probably the last 
lot that will be found in this district. 
A large number of other choice Cornish 
specimens. 
RUSSELL & SHAW, 
38 Gt. James Street, Bedford Row, London, W.C, 
THE 
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