ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 387 



very clearly how the same apparatus, which creates the relief of retinal 

 images by dissociating them, improves them by bringing these images 

 into another combination. 



Fran(,-ois-Franck, Gii.-A. — Note generate sur les prises de vues instantanees 

 microphotographiques (plaque fixe a pellicule) avec l'arc volta'ique. 



C.R. Soc. Biol. Paris, lxii. (1907) p. G57. 



Nbuhauss, R. — Lehrbuch der Microphotographie. 



Leipzig (S. Hirzel) 1907, xvi. and 273 pp. (3 pis., 63 figs.). 



Pinoy, E. — Nouvel appareil de miorophotographie : possibility d'obtenir meme a de 

 forts grossissements, une image donnant l'idee de la structure d'objet presentant 

 une certaiue epaisseur. C.R. Soc. Biol. Paris, lxi. (190G) pp. 552-4 (1 fig.). 



Siede, W. — liber einen einfachen Mikrophotographischen Apparat. 



Zeitschr. f. angew. Mikrosk., xiii. (1907) p. 62. 

 Swingle, W. T., & L. T. Briggs — Improvements in the Ultraviolet Microscope. 



Science, n.s. xxvi. (1907) p. 180. 



(5) Microscopical Optics and Manipulation. 



Application of the Ultramicroscope (after Siedentopf) and of the 

 Microspectral Photometer (after Engelmann) to the Textile and 

 Dyeing Industries. — N. Gaidukov has investigated the above subject 

 in regard to a great variety of materials, and states his conclusions 

 as follows : — 



1. By means of Siedentopf s ultramicroscope it is possible to test the 

 qualities of woven threads, and to detect the sources of these qualities. 



2. By means of Engelmann's spectral-photometer it is possible to 

 examine the smallest particle of dye-stuff ; to arrive at a chromatic 

 analysis (qualitative and quantitative) of individual threads ; to com- 

 pare the colour peculiarities of the dye and of the threads dyed with it ; 

 to observe the spectra of several adjacent threads ; and to compare with 

 one another the intensities of the tint of several threads of the same 

 material. 



The author does not regard his results as exhaustive, but rather as 

 suggestive of a very promising field for exploration. 



Heimstadt, O. — Spiegelkondensor fur ultramikroskopische Beobachtungen. 



Zeitschr. f. Chemie u. Industrie d. Kollo'ide, i (1907) heft 9. 



Cleric i, E. — Sulla determinazione dell'indice di refrazione al microscopio. 



Atti delta R. Accad. dei Lincei, xvi. (1907) p. 336. 



Faure-Fremiet, E. — Sur l'etude ultramicroscopique de quelques protozoaires. 



C.R. Soc. Biol. Paris, briv. (1908) pp. 582-4. 



Gatin-Gruzewska, Z., A. Mater, & G. Schaepfer— Sur la structure 

 ultramicroscopique des empois d'Amidon et de leurs constinants. 



Tom. cit., pp. 599-601. 



Siede, W. — Ein neuer Apparat zur Sichtbarmachung ultramikroskopischen 

 Teilchen. Zeitsclir. f. angew. Mikrosk., xiii. (1907) p. 79. 



Schuster, A. — Einfuhrung in die Theoretische Optik Autorisierte, deutsche 

 Ausgabe, iibersetzt von H. Konan. 



Leipzig und Berlin (B. G. Teubner) 1907, xiv. and 413 pp. 



(2 pis. and 185' figs.) 



* Zeit. f. Ang. Chemie und Zentralbl. f. Technische Chemie, xxi. (1908) p. 393 

 et seq. (1 pi. and 1 fig.). 



2 D 2 



