466 SUMMAEY OF CUERE1?T RESEARCHES RELATING TO 



Scott, G. B.— Polarizer for the Microscope. 



[Analyser mounted in a tube on a swivel just over the nose-piece so that it 

 can be " pushed over to one side out of the way by a lever " when not in 

 use. Polarizer also mounted on a short arm beneath the stage. Micro- 

 scopes with narrow tubes must have a recess into which the analyser can 



Engl Mech., XXXIX. (1884) p. 173 (2 figs.). 

 Stein, T. — Die Verwendung des elektrischen Gluhlichtes zu mikroskopischen 

 Untersuchungen und mikrophotographischen Darstellungen. (The application 

 of the electric incandescence light for microscopical investigations and photo- 

 micrography.) [Fost-I 



Zeitschr. f. Wiss. Mikr., I. (1884) pp. 161-74 (7 figs.). 

 Stowell, 0. H.— Our third Annual Soiree. The Microscope, IV. (1884) pp. 63-4. 

 ,, ,, An Editor's Life. 



[Letter from a microscopist who " finds the working of the Microscope very 

 pleasant employment for the evening of life."] 



The Microscope, IV. (1884) p. 105. 

 Swammerdam, John, Sketch of his Life and Eesearches. 



Journ. of Sci., VL (1884) pp. 198-206, 

 Tait, P. G.— Light, viii. and 276 pp. and 49 figs. [Microscope, pp. 113-6.] 



8vo, Edinburgh, 1884. 

 VoGEL, J. — Das Mikroskop und die wissenschaftliche Methode der mikro- 

 skopischen Untersuchung in ihrer verschiedener Anwendung. 4th ed. By 

 O. Zacharias. Lfg. 1. Leipzig, 1884. 

 Wanschaff, J. — Ueber eine neue Methode zur Anfertigung sehr langer Mikro- 

 meter-schrauben. (On a new method of constructing very long micrometer 

 screws. [_Fost.2 Zeitschr. f. Instrumentenk., IV. (1884) pp. 166-9. 



Ward, E. H. — An Eye-shade for Monocular Microscopes. [^Post.'] 



Amer. Mon. Micr. Journ., V. (1884) pp. 82-3 (1 fig.). 

 Wassell, H. A. — Plate Glass for Optical Purposes. 



Ungl. Mech., XXXIX. (1884) pp. 170-1. 

 WiEDERHOLD. — See Puscher. 

 Zachabias, O. — See Vogel, J. 



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



Dissection of Aphides.* — G. B. Buckton says that " in the dissection 

 of Aphides much assistance may be often got by a selection of 

 liquids. Some of these are best suited for the purpose of hardening 

 the tissues, so that they may bear separation and tearing asunder 

 without their destruction. Others are used for colouring the trans- 

 parent organs, so as to make them more visible. These organs of 

 Aphides are so delicate that pure water will in a great measure destroy 

 them. In such cases a weak solution of common salt, or very dilute 

 glycerine, or sugar and water, or albumen and water, all of which 

 should nearly approach the density of the juices of the insect, will be 

 found a considerable help. 



Some Aphides are so large, so full of liquid, and so charged with 

 oil-globules that some treatment is necessary to reduce their bulk, 

 and to allow of a sufficiently thin stratum of balsam for mounting. 



In such cases the Aphides may be placed in spirits of turpentine, 

 and just raised to the boiling-point in a small test-tube. After soaking 

 in the turpentine for a few hours, all the oil-globules will be removed, 



* ' Monograph of the British Aphides,' iv. (1883) pp. 193-5. 



