ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 633 



Stein, S. T. — Das Mikroskop uud die mikiographische Technik zum Zwccke 

 pliotographischer Darstellung. (The Microscope aud Microscopical Technic 

 In Photographic representation.) Part II. of ' Das Licht im Dienste 

 wissenschaftlicher Forschung,' 2nd ed., pp. i.-ix. aud 151-322, figs. 168-302, 

 pis. iii-vi. 8vo, Halle a. S., 1884. 



Stowell, C. H. — Kochester meeting [of American Society of Microscopists]. 



The Microscope, IV. (1884) pp. 131-2. 



Strasbckgek, E. — Das botanische Practicum. Anleitung ziim Selbststudium der 

 mikroskopischen Botanik fiir Anfanger uud Fortgeschrittneu. (Practical 

 Botany. Guide to the study of microscopical Botany for begiuuers and 

 advanced students.) xsxvi. and 664 pp., and 182 figs. 8vo, Jena, 1884. 



Talbot, R. — Das Scioptikon, VervoUkommueter Projectionsapparat fiir den 

 Unterricht. 7th ed., vi. aud 82 pp. 8vo, Berlin, 18S4. 



[Mainly a Catalogue of Photograms aud microscopical preparations. ] 



Thtrston, E. — The Microscope : its Construction and Manipulation. 



Micr. News, IV. (1884) pp. 150-2. 

 Waters, W. H. — Histological Notes for the use of Medical Students, vi. and 

 65 pp. 8vo, Manchester and London, 1884. 



[The body-tube of the Microscope is (not aptly) styled the " telescope-tube '" ! 

 and the concave mirror the " curved mirror."] 

 Wenham Button. 



[To keep the Wenham button or the common hemispherical lens in position 

 while examining temporary mounts, fix it with glycerin or immersion 

 fluid to that surface of a slide on which has been turned a wax or an 

 asphalt ring, the internal diameter of which corresponds to the diameter 

 of the lens. Invert the slide, and it is ready for use.] 



T/ie Microscope, IV. (1884) p. 134. 



/3. Collecting, Mounting and Examining Objects, &c. 



Methods of Investigating Animal Cells.* — Dr. A. Brass has de- 

 voted several years of close study to the structure and life of animal 

 cells, and gives a detailed account of his methods. The following 

 are some of the more important of these methods : — 



1. Protozoa. — As most Protozoa move very rapidly when hungry, 

 it is well to feed them before attempting to study them with the 

 Microscope. If well fed with powdered pieces of plants, &c., they 

 usually remain quiet after a short time, and begin to assimilate the 

 food-material which they have appropriated. In this condition of 

 comparative quiet they can be easily examined with high powers. 

 For this purpose they may be placed under a cover-glass with a 

 considerable quantity of water and a number of small green algae to 

 keep the water supplied with oxygen. 



For higher powers Abbe's illuminating apparatus is extremely 

 useful. In some cases it is desirable to have a completely one-sided 

 illumination, and this is best effected by inserting beneath the 

 illuminating apparatus a circular diaphragm- plate perforated with 

 a slit 3 mm. wide that runs parallel to the edge of the plate. It 

 is best to leave about 2 mm. between the slit and the edge of the 



* Zeit^^hr. f. Wisn. Mikr., i. (1884) pp. 39-51. Cf. Amer. Nalural., xviii. 

 (1884) pp. «.')0-l. 



Sor. 2.— Vol.. IV. 2 U 



