ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 159 



can see simultaneously all the lines of the objects in the field well defined and 

 resolved, then his eye is practically without astigmatic defect. The object of 

 this important test-slide is very obvious, as incomplete perceptions are often 

 erroneously attributed to the inferiority of the objective used, when in fact they 

 are the result of an astigmatic defi ct in the observer's eye. Results of observa- 

 tions among microscopists often differ because the operators of instruments are 

 frequently not aware of the astigmatic condition of their eyes."l 



A7ner. Hon. Micr. Journ., Vll. (1886) p. 220. 

 C ZAP SKI, S. — Mittheilnngen iiher das glastechnische Laboratorium in Jena und die 

 von ihrn hergestellten neuen optischen Glaser. (On the Jena Glass Laboratory and 

 the new kinds of optical glass made there.) 

 [Cf. Journal, 1886, pp. 316 and 849.] 



Zeitschr. f. Instrumentenh., VI. (1886) pp. 335-48 (2 figs.) concluded. 

 D. — The Value of the Microscope in Trade. [5"/ira, p. 157.] 



Engl keck, XLIV. (1886) pp. 391 (3 figs.). 

 D E B E s, E. — Hilfsapparat zum Anssnchen nnd Legen von Diatomaceen. (Apparatus for 

 selecting and placing diatoms.) [Supra, p. 158.] 



Zeitschr. f. Wiss. Mikr., III. (1886) pp. 330-6 (3 figs.). 



DiDELOT, L. — Du pouvoir amplifiant du Microscope. Determination theoriqne et 



experimentale. (On the magnifying power of the Microscope. Theoretical and 



experimental determination.) 54 pp. and 1 pi., 4to, Lyon, 1886. 



DiPPEL, L. — Die apochromatischen Objective und Compensationsoculare von Carl 



Zeiss, (The apochromatic objectives and compensation oculars of Carl Zeiss.) 



[Cf. Journal, 1886, pp. 316 and 849.] 



Zeitschr. f. Wiss. Mikr., III. (1886) pp. 303-19. 

 DoEST, F. J. — TJeber die Grosse der Beobachtungsfehler beim Ablesen eingetheilter 

 Instrumente. (On the extent of the errors of observation in reading-off divided 

 instruments.) [_Sujora, p. 155.] 



Zeitschr. f. Instrumentenk., VI. (1886) pp. 383-7. 

 Evans, F. H. — Photo-micrography, [Post.'] 



Journ. and Trans. Phot. Soc, XL (1886) pp. 25-9 (1 fig.). 

 Gage, S. H. — Microscopical Notes. 



[1, 2, and 3, see /8. 4. Paper for cleaning the lenses of objectives and oculars, 

 post. 5. See /3.] 



The Microscope, VI. (1886) pp. 265-8 (2 figs.). 

 Glass, the New. [Supra, p. 155.] Micr. Bulletin {Queen's), III. (1886) pp. 35-6. 



Grunow's Physician's Microscope. [Post.'] The Microscope, VI. (1886) p. 245 (1 fig.). 



Heukck, H. van. — Notice sur une serie de photomicrogrammes faits en 1886. Note 

 sur les chamhres photographiques jointes a I'envoi, (Note on a series of photomicro- 

 graphs made in 1886. Note on the photo.graphic cameras accompanying.) [See 

 infra, p. 182.] 



Bull. Soc. Belg. Micr., XIII. (1886) pp. 5-11. 

 HiLDEBEAND, H. E. — TJeber einen einfachen und sehr gebrauchsfahigen Objectfiihrer. 

 (On a simple and very useful object-carrier.) [Supra, p. 154.] 



Zeitschr. f. Wiss. Mikr., III. (1886) pp. 386-9 (3 figs.). 

 Hillhouse, W. — See Strasburger, E. 

 James, F. L. — American Society of Microscopists — The Chautauqua Meeting. 



[Report of the meeting and editorial comments on tlie apathy of the Chautauqua 

 people, and on the conduct of a member who at the Soire'e exhibited to a mixed 

 assemblage " living " human spermatozoa, under the description of " the germs 

 of life."] 



St. Louis Med. and Surg. Journ., lA. (1886) pp. 153-7. 

 „ „ Ditto. 



[" Mr. E. H. Griflith, of Fairport, N.Y., the originator and for several years past the 

 superintendent of the Working Session of the American Society of Microscopists, 

 is very much chagrined at a mistake which occurred at Chautauqua, and which 

 cost him and the Society several valuable books, slides, and instruments. 

 Having received from California some microscopical material for distribution, 

 he announced the fact in open session, and told all who desired specimens to 

 come to his table and help themselves. Quite a number of persons availed 

 themselves of the offer and helped themselves, not only to the unmounted 

 material, but to a large number of rare and costly mounted slides belonging to 

 the Society, and some valuable books which chanced to be on the same table. 

 Similarly, Mr. Griffith's offer to loan any instrument on his table to workers in 

 the session, was taken to mean that the parties could keep what they borrowed 

 — the result being a nett loss of four new and costly Griffith's turntables. No 

 doubt those who took the books and slides did so under a misunderstanding of 



