OcTOBER 30, 1913] 
NATURE 
xciil 
LANTERN SLIDES. }| WATKINS & DONCASTER, 
Large Stock for Sale or Hire of 
NATURE PHOTOGRAPHS. 
British Birds, Flowers, and Insects. 
GEOLOGICAL PHOTOGRAPHS. 
Scenery—Specimens—Photomicrographs. 
ASTRONOMY. 
Slides made to order from Negatives, Prints, 
Drawings, &c. Prompt Deliveries. 
FLATTERS & GARNETT, LTD., 
309 Oxford Road (°grvits the), Manchester. 
Sales by #uction. 
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 
urchase of SCIENTIFIC AND ELECTRICAL APPARATUS, 
Riiercebcoes and Accessories, Surveying Instruments, Photographic 
Cameras and Lenses, Lathes and Tools, Cinematographs and Films, 
and Miscellaneous Property. ? 
Catalogues and terms for selling will be forwarded on application to 
Mr. J. C. STEVENS, 
38 KING STREET, COVENT GARDEN, LONDON, W.C. 
ROCK SECTIONS FOR THE MICROSCOPE 
New List of over 600 well cut Rock and Mineral 
Sections now ready, post free from 
JAMES R. GREGORY 6& CoO., 
Mineralogists, Gc., 
139 FULHAM ROAD, SOUTH KENSINGTON, S.W. 
Telegrams: ‘‘ Meteorites, London." 
Telephone : 2841 Western. 
LIVING SPECIMENS FOR 
THE MICROSCOPE. 
Volvox, Spirogyra, Desmids, Diatoms, Amoeba, Arcella, Actinospherium, 
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 be supplied, either living 
or preserved by the best methods :— 
Sycon; Clava, Obelia, Sertularia; Actinia, Tealia, Caryophyllia, 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. 
For prices and more detailed lists apply to 
Biological Laboratory, Plymouth. THE DIRECTOR 
Naturalists and Manufacturers of 
CABINETS AND APPARATUS 
FOR COLLECTORS OF INSECTS, BIRDS' EG@GS 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.) 
FOLL OATALOGUE POST FREE. 
FOR ALL KINDS OF EDUCATIONAL 
Mineral Material, 
COMMON ORES, and SELECT CRYSTALLIZED 
SPECIMENS, at ALL PRICES. 
G. H. RICHARDS & CO., 
Dealers in all kinds of British and Foreign Mineral Specimens. 
Note new Address :— Lists free. 
48 Sydney Street, Fulham Road, South Kensington, London, S.W. 
SKELETONS ®& SKULLS a 
Specimens and Preparations for Teaching i 
BIOLOGY & ZOOLOGY 
and for Museums. 
Lists on Application. 
EDWARD GERRARD & SONS 
Osteologists and Taxidermists, 
NATURAL HISTORY STUDIOS 
6I College Place, 
Camden Town, London. 
A Small Lot of the New and Rare Indian 
WINE RAILS 
WINCHITE, TILASITE, 
and 
HOLLANDITE 
Now on Sale at 
RUSSELL a SHAW, 
38 Gt. James Street, Bedford Row, London, W.C. 
NOTICE.—Advertisements and business letters for ‘‘ Nature” should be addressed to the Publishers; Editorial Com. 
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Cloth Cases for binding “‘ Nature” are issued at 1s. 6d. each, and can be sent post free for ls. 9d, 
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