— 
FEBRUARY 12, I9I4] 
NATURE 
ccxlvii 
MINERALOGY—CRYSTALLOGRAPHY— 
PETROGRAPHY—GEOLOGY. 
Ask for our new 
GENERAL CATALOGUE XVIII. 
(2nd Edition) 
for the use of Middle and High Schools and Universities. 
Part I, 260 pages, 110 IIlustrations. 
This catalogue has been prepared 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 point 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. 
BRITISH FOSSILS. 
JAMES R. GREGORY & CO. have a large stock of Fossils. 
The recent addition include specimens from the Wealden, 
Coal Measures, and Silurian Formations, including some 
good Trilobites, 
JAMES R. GREGORY & CoO., 
Mineralogists, &c., 
1389 FULHAM ROAD, SOUTH KENSINGTON, S.W. 
LIVING SPECIMENS FOR 
THE MICROSCOPE. 
Volvox, Spirogyra, Desmids, Diatoms, Amceba, 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. 
WATKINS & DONCASTER. 
Naturalists and Manufacturers of 
CABINETS AND APPARATUS 
FOR COLLECTORS OF INSECTS, BIRDS’ EGGS AND SKINS, 
MINERALS, PLANTS, &c. 
BIRD NESTING BOXES of various patterns. 
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 CATALOGUE POST FREE. 
WINERALS. 
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. 
xX-RAY TUBE, 
Price 15/= 
Sole Maker, 
H. LM, 
66 Hatton Carden, 
London. 
ACTUAL MAKER 
of all kinds of 
X-Ray and Vacuum 
Tubes, &c. 
LIST FREE. 
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