/ 
‘FEBRUARY 22, 1917] 
NATURE 
CXCix 
LANTERN SLIDES 
Large stock of Natural History and 
Scientific Subjects. 
SEND FOR CATALOGUES Exz and E13. 
Slides also made to order from originals 
of all kinds; 
FLATTERS & GARNETT, Ltd., 
309 OXFORD ROAD (,0pzrts), MANCHESTER. 
best possible results. 
HARLING’S NEW ‘“‘ACRIBO” 
SECTIONAL PAPER & PADS 
COMBINE 
ABSOLUTE ACCURACY—GOOD PAPER—LOW PRICE 
No. 1: inches and 8ths. No. 2: inches and 1oths. 
No. 3: centimetres and millimetres. 
Price of either, 50 sheets in a pad with cover, 2/6. 
NEW __LINE :—Sheets, printed on Thin Linen Bank, in 
same three scales, at 1/3 per quire. 
De Nartorz says: ‘‘ The paper is excellent, the ruling is accurate, the 
* pad is convenient, and the production is British throughout.” 
See also further editorial notice, Dec. 7, 1916, p. 277- 
Write for free specimens and compare accuracy with any in use. 
W. H. HARLING, ““initrument Mauitacturer 
(Bttab. 1851) 47 FINSBURY PAVEMENT, LONDON, E.C. 
LIVING SPECIMENS FOR 
THE MICROSCOPE. 
From various causes, owing to the war, T. B. finds he cannot supply his 
<orrespondents with the usual promptitude; he considers it best to 
temporarily suspen the Agency. 
HOMAS BOLTON, 
25 BAESALL 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 ; 3 Clava, Obelia, Sertularia; Actinia, Tealia, Caryophyllia, Alcy- 
onium; Hormiphora (preserved) ; ; Leptoplana; Lineus, Amphiporus, 
Nereis, Aphrodite, Arenicola,, Lanice, Terebella; Lepas, Balanus, 
Gamunarus Ligia Mysis, Nebalia, Carcinus; Patella, Buccinum, Eledone, 
Pectens Bugula, Crisia, Pedicellina, qfislothuria, Asterias, Echinus, 
Salpa (preserved), Scyllium, Raia, &c., &c. 
For prices and more -detailed lists apply to 
Biological Laboratory, Plymouth. 
THE DIRECTOR. 
NOTICE.—Advertisements and business letters for ** Nature” 
The telegraphic address of ** Nature”’ 
Editorial Communications to the Editor. 
Telephone—Gerrard, 8830. 
’ : SUBSCRIPTIONS 
BOE ee A 
Pe a a 
0 14 6 
OF r2a46 
Yearly 
Hialf-yearly (26. Numbers) 
Quarterly (13 Numbers)... 
WATKINS & DONCASTER. 
Naturalists and Manufacturers of 
CABINETS AND APPARATUS 
FOR 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, &ec., Preserved and Mounted by First-class 
Workmen true to Nature. 
All Books and Publications (New and Second-hand) on Inseets, 
Birds’ Eggs, &c., supplied. 
86 STRAND, LONDON, W.C. 
(Five Doors from Charing Cross.) 
FULL CATALOGUE POST FREE 
MICROSCOPICAL SECTIONS 
TYPICAL ROCKS. 
12 Sedimentary and Metamorphic, in box 
12 Igneous, in. box ... ey 
2 Sets, as above, '35/- 
18/- 
18/- 
Sections to order, 1/6 each. 
RUSSELL & SHAW, 
38 GT. JAMES STREET, BEDFORD ROW, LONDON, W.C. 
BRITISH FOSSILS. 
JAMES R. GREGORY & CO. have a large stock of the 
above, to which they are constantly adding new material. 
Specimens can be supplied in sets for Teaching purposes, and 
specimens for Demonstration and Museums can be had. 
JAMES R. GREGORY & CO., Mineralogists, &c., 
1389 FULHAM ROAD, SOUTH KENSINGTON, S.W. 
Telegrams: ‘‘ Meteorites, London.” Telephone: Western 2841. 
GLASS BLOWING 
ALL KINDS OF SCIENTIFIC AND EXPERIMENTAL GLASS 
BLOWING carried out quickly and correctly from rough sketch 
at Moderate Charges. 
ANY FORM OF GLASS APPARATUS REPAIRED. 
DEMONSTRATIONS given here, or at Colleges, &c. 
66 HATTON GARDEN, LONDON, 
H. HELM, Telephone: 2512 Holborn. 
ACTUAL MAKER of ALL K/NDS of X Ray, Geissler and other 
Vacuum Tubes, Mercury Pumps, High Frequency Electrodes, &€. 
List free. 
should be addressed to the Publishers; 
is ‘‘Phusis,” London. 
TO “NATURE.” 
To all Places Abroad :— 
Yearly 
Half-yearly (26 Numbers) 
Quarterly (13 Numbers)... 
(A charge of 6d. is made for changing Scotch and Irish Cheques.) 
Cloth Cases for binding ‘‘ Nature” are issued at ls. 6d. each, and can be sent post free for 1s. 9d, 
ee ES 
NET eas rel ri ADVERTISEMENTS. 
aoe 
9 
0 
ig 6 
First Two Lines in Column ... 
Per Line after .. 
One Sixteenth Page, or Eighth Col. 
One Eighth Page, or Quarter Col.... 
o 
0 
0 
0 
One Sixth Page, or One Third Col. 
Quarter Page, or Haif a Column ... 
Half a Page, ora a 
Whole Page 
AWM et, 
For the re-direction of replies to advts. a charge of 3d. per nea: re cadeliy 
Cheques and Money Orders should be Crossed and made payable to MACMILLAN @ CO., Limited. 
OFFICE: ST. MARTIN’S 
STREET, LONDON, W.C. 
