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Guide to the Science of Photo-Micrography. By Edward 



C. Bousfield, L.R.C.P. London. 8vo, pp. xv. — 174. (London : J. & A. 

 Churchill. 1892.) Price 6s. 



This is a second edition, entirely re-written and much enlarged. The 

 author gives special consideration to the difficulties usually met with in 

 histological and bacteriological work, and has introduced a new section, in 

 which he deals in extenso with the method of photographing cultures; a number 

 of good illustrations of photo-micrographic cameras, etc., are given. The 

 book will unquestionably be found of much assistance to those interested in 

 the subject. 



Medical Microscopy : A Guide to the use of the Micro- 

 scope in Medical Practice. By Frank J. Wethered, M.D. London. Crown 

 Svo, pp. XX. — 412. (London: H. K. Lewis. 1892.) Price 9s. 



Some very useful hints for the microscopist are given here, whether or not 

 he belongs to the medical profession, but for the medical practitioner or 

 student it will prove invaluable. It treats of the most simple methods of pre- 

 paring micro-sections, and of the examination of urinary deposits, sputa, blood, 

 etc. Elaborate methods are also given for the examination of foods and 

 bacteriological studies. There are upwards of 100 illustrations. 



Untersuchungen uber Mikroskopische Schaume und 



das Protoplasma, von O. Biitschli. 4to, pp. iv. — 244. (Leipzig : Wilhelm 

 Engelmann. 1892.) Price 24 marks. 



This is an exposition of the author's "foam theory " of the structure of 

 protoplasm. He first gives a very elaborate investigation into the formation 

 and properties of microscopical foam, which may be produced in various ways, 

 but after many experiments the best results were obtained from a mixture of 

 olive oil and carbonate of potash. The fine froth thus produced simulates the 

 movements of protoplasm in a remarkable manner ; when a drop is examined 

 upon a warm stage under the microscope, characteristic amosboid changes take 

 place, and vigorous currents are set up. The explanation of the cause of these 

 movements are given. Then follows a description of the structure of proto- 

 plasm in various organisms, and a critical examination of tlie various hypotheses 

 which have been advanced to explain vital action. The author is of opinion 

 that the structure of protoplasm corresponds to that of ordinary foam, with 

 this difference, that the minute cavities in protoplasm are filled with a watery 

 fluid instead of air, as in the foam. An exhaustive bibliographical list of 

 works consulted is appended. The book is illustrated with six litho-plates and 

 23 wood engravings. 



Die Naturlichen Pflanzenfamilien. By A. Engler and 

 K. Prantl. Parts 72, 3, 4, 5. (London : Williams and Norgate. Leipzic : 

 Wilhelm Engelmann.) 



In these four parts thirteen orders are described, and very capitally illus- 

 trated by 98 woodcuts, containing 709 figures. 



British Fungus-Flora : A Classified Text-book of Mycology. 

 By George Massee. In three vols. Vol. I. Crown Svo, pp. xii. — 432. 



This volume deals exclusively, and somewhat exhaustively, with the 

 Basidiomycetes groups of fungi. The opening chapter gives an account of the 

 nature and origin of Fungi. There are several woodcuts, illustrating more than 

 100 species. 



