( 13 ) 
POWELL -A.LTID LEALAlsTD, 
170, EUSTON ROAD, LONDON, N.W. 
MANUFACTURERS OF MICROSCOPE STANDS, OBJECT-GLASSES, 
CONDENSERS, &c. 
A NEW rVin- APOCHROJVIATIC HOMOGENEOUS IMMERSION, 
1-40 N.A., PRICE £15. 
This Objective is a Rapid Photographer. 
CATALOGUES FREE ON APPLICATION. 
Post Free for Four Stamps. 
A New Classified Catalogue ( No. ioS) of 
Important Works for Sale on 
BOTANY: 
PART. III. CRYPTOGAMIC BOTANY. 
Containing Desmids and Diatoms. Algse, Characese, and Confervae. 
Lichens. Fungi and Microfungi. Mosses and Hepaticae. Ferns. 
Botanical Microscopy and Works on the Microscope. 
WILLIAM WESLEY & SON, 28, Essex Street, Strand, London. 
SHORTLY WILL BE PUBLISHED. 
JOHN - WHELDOLT 3 S 
CATALOGUE OF BOTANICAL WORKS AND PAPERS, 
PART II. 
CONTAINING FERNS, FLORAS, ETC. 
Sent post-free for 2 stamps. 
LONDON: 58, GREAT QUEEN ST., LINCOLN’S INN FIELDS, W.C. 
JUST PUBLISHED. Price, Cloth 2s., Boards Is. 6d. 
PHOTOGRAPHY APPLIED TO THE MICROSCOPE. 
By F. W. MILLS, 
MEMBER OF THE CAMERA CLUB, THE HUDDERSFIELD PHOTOGRAPHIC SOCIETY, 
THE POSTAL MICROSCOPICAL SOCIETY, ETC. 
This book contains practical instructions intended for scientific men who desire to 
preserve their microscopical observations by means of photomicrography, without devoting 
considerable time to the science of photography. 
London : ILIFFE & SON, 3, St. Bride Street, Ludgate Circus. 
THE BRITISH MOSS FLORA. 
By R. BRAITHWAITE, M.D. 
Part X., Tortulac®, price 10s. Subscriptions to Sect. 4 (10s. 6d.) may be sent to the 
Author. Vol. I., price £2 10s., is published by 
LOVELL REEVE & CO., 5, HENRIETTA STREET, COVENT GARDEN. 
