332 SUMMARY OF CURRENT RESEARCHES RELATING TO 



plato turned end for end ; but it is best to always place the plate in the 

 bolder in the same position, and change the mat to expose successive 

 quarters, but this requires the camera to be moved for each exposure. 

 Monocular Stereoscopic Vision.* — Prof. Fritsch describes an 

 optical phenomenon observed during the microscopical examination 

 of certain objects, and which he considers is due to monocular stereo- 

 scopic vision. Certain images, in particular those of the transverse 

 section of the principal nerves of the electric organ, give the idea 

 of a funnel-shaped depression, such as is otherwise obtained only in 

 binocular stereoscopic vision. He found it especially easy to receive 

 this impression by moving the eye from side to side. 



Journal of the New York Microscopical Society. — "Wo are glad 

 to welcome this new microscopical journal. While every addition to 

 the number of new journals adds to the strain which is put upon both 

 space and time so far as we are concerned, it is, we think, clearly to 

 the advantage of the cause of microscopy that there should be a 

 fair nimiber of microscopical journals. Nearly all those published 

 hitherto have at one time or another been the means of adding to our 

 knowledge to no inconsiderable extent. 



Strasburger's Practical Botany. f — E. Strasburger supplies an 

 extremely useful handbook for practical botanical students. The 

 smaller work is intended for beginners only. The larger one is printed 

 in two different types. The paragraphs in larger type are adapted 

 for beginners, and those in smaller type for more advanced students, 

 the whole being arranged in thirty-four " lessons " for a six-months' 

 course. The introduction to the larger work deals with Microscopes 

 and all other apparatus, reagents, &c., necessary for workers in the 

 botanical laboratory. In the lessons themselves, plants are in general 

 chosen which are readily accessible ; and the mode of treatment is 

 described best calculated to bring out the various important points in 

 their structure. The whole is illustrated by admirable woodcuts. 



Microscopical Societies.^ — E. Hitchcock discusses the fact that 

 microscopical societies are " vigorous for a time, then they gradually 

 languish, and sometimes disband. There is scarcely an exception to 

 this rule." He considers the remedy to be to make the meetings of 

 value and interest to the members. 



" If the meetings are to be interesting and instructive, somebody 

 must work to make them so. It involves no little labour on the part 

 of the few who undertake to conduct a successful society. Still the 

 time thus spent is not without profit both to the individual and to the 

 members. One need not be thoroughly informed upon microscopical 

 subjects to be an efficient leader. It requires energy, interest, and a 

 willingness to work, more than anything else. Let those who are 

 willing to give their time and work for the benefit of others who do 



* Nature, xxxi. (1885) p. 212. 



t Strasburger, E., 'Das BotanisdiePracticum,' xxxvi. and 664 pp. (182 figs.). 

 ' Das Kleine Botanische Practicum fiir Anfanger,' viii. and 285 pp. (114 figs.), 

 gvo. Jena, 1884. 



X Amer. Mod. Micr. Joum., v. (1884) pp. 215-7, 237-8. 



