STOCK-CULTURES, ETC.; COLOR-CHARTS; PHOTOGRAPHY, ETC. 



263 



('93)- HAUSER, G. Ueber Verwendung des For- 

 malins zur conservirung von Bacteriencul- 

 turen. Miinchen. nied. Wochenschr., 1893. 

 Bd. xr., pp. 567-568. Rev. in Centralb. f. 

 Bakt, Bd. xiv, 1893, p. 290. 



Ten or fifteen drops of fresh formalin are put on filter 

 paper and placed tinder the cover of the Petri-dish cul- 

 ture. This is then exposed to the vapor of formalin in a 

 close room lined with wet filter paper, 15 drops of forma- 

 lin being 1 placed on cotton and introduced for each 1000 

 cc. of air space. As the formalin penetrates the deeper 

 layers of gelatin only slowly, a thin layer should be used 

 for liquefying: organisms. The formalin should be 

 allowed to act for several days, and be renewed once or 

 twice. The gelatin appears to be permanently disin- 

 fected, will not melt at any temperature, and is un- 

 changed in appearance. To have permanent preparations 

 it is only necessary to keep them from drying out. 



fy.3). HAUSER, G. Weitere Mitteilungen iiber Ver- 

 wendung des Formalins zur conservirung 

 von Bacterienculturen. Miinchen. med. 

 Wochenschr., 1893, Bd. XL, pp. 655-656, No. 

 35- Rev. in Centralb. f. Bakt., Bd. xiv, 1893, 

 pp. 468-469. 



Describes a method of fixing and mounting colonies 

 taken from gelatin plate cultures. 



('94). KRUECKMANN. EMU.. Eine Methode zur Her- 

 stellmig bakteriologischer Mttseen ttnd Kon- 

 servierung von Bakterien. Centralb. f. 

 Bakt, Bd. xv, 1894, pp. 851-857. 



Fixes cultures with mercuric chloride, etc., and pre- 

 serves them in formalin, air-tight, in the dark. 



('97). FAKES, W. C. C., AND EYRE, J. W. Formalin 

 as a preservative for cultivations of bac- 

 teria. Jour, of Path, and Bact., vol iv, 1897, 

 pp. 418-420. Also a separate, 3 pp. 



('oi). CONN, H. W. How can bacteria be satisfac- 

 torily preserved for museum specimens? 

 Science, n. s., vol. xin, 1901, p. 326. 



LIII. Stock-Cultures, How Best Kept; Vitality on 

 Media. 



('89). CZAPI.EWSKI, E. Zur Anlage bakteriologischer 

 Museen. Centralb. f. Bakt., vi Bd.', 1889, 

 pp. 409-411. 



This method consists in limiting the amount of air 

 which can reach the culture by saturating the upper part 

 of the cotton plug with melted paraffin. The chief objec- 

 tion to it is the increased difficulty of cleaning the dis- 

 carded tubes. 



('98). LUNT. On a convenient method of preserving 

 living pure cultures of water bacteria. Rev. 

 in Centralb. f. Bakt., xxm Bd., 1898, pp. 

 795-796. 



Certain water-bacteria may be kept alive for two years 

 or more in sterile water, i. e. much longer than in ordi- 

 nary culture-media. 



('oo). BOLLKY, HENRY L. The duration of bacterial 

 existence and [in ?] trial environments. 

 Centralb. f. Bakt., 2 Abt, vi Bd., 1900, pp. 

 33-38. 



Reports getting a good growth of Bacillus amylovorns 

 and Bact. dianthi in agar and bouillon by transfers from 

 cultures which had been hermetically sealed for 9 years. 

 Tests of the pathogenic power of these cultures appear 

 not to have been made. 



('oi). SCHUI.TZ. See vi. 



LIV. Color-Charts ; Nomenclature of Colors. 



('86). RIDGWAY, ROBERT. Nomenclature of colors 

 for naturalists. 195 water colors on ten 

 plates, with rules for making the same and 

 a general discussion of colors. Boston, Lit- 

 tle, Brown & Co., 1886. 



Valuable, but out of print. Especially useful on 

 account of the number of colors. Another edition in 

 preparation. 



('94). SACCARDO, P. A. Chromotaxia sen nomen- 

 clator colorum polyglottus additis speci- 

 minibus coloratis ad usum botanicorum et 

 zoolpgortim. 2d ed. Padua. Typis Semi- 

 narii, 1894, 8vo., 22 pp., with two tables con- 

 taining 50 colors. 

 A cheap and useful color scheme for botanists. 



('95). Color chart under Spectrum, in the Standard 

 Dictionary, Funk and Wagnalls, New York, 

 1895- 

 This may be had separately. 



('95). SHUTTLEWORTH, E. B. Nomenclature of col- 

 ors for bacteriologists. Jour. Am. Pub. 

 Health Asso., Oct., 1895, Annual vol. xx, 

 pp. 403-407. 



('98). PRANG, Louis. The Prang standard of color. 

 Popular ed., Boston, 1898. Folio. 



C ) Chart of Spectrum Scales made from the 

 Bradley colored papers. Milton Bradley 

 Co., Springfield, Mass. A small sheet (about 

 3/4x754 inches) with 90 colors. Also a 

 large folded chart (11x28 indies). 



Colors are bright, but must be carefully protected from 

 the light. 



LV. Photography and Photomicrography. 



C/7). KOCH, ROBERT. Verfahren zur Untersuchun- 

 gen, zum Conserviren und Photographiren 

 der Bacterien. Cohn's Beitrage, II Bd., 3 

 Heft, Breslau, 1877, pp. 399-434, with 24 

 photomicrographs on 3 plates. 



('81). KOCH, R. Zur Untersuchung von pathogenen 

 Organismen. Mitth. aus dem Kais. Gesund- 

 heitsamte, Bd. I, 1881, pp. 1-48. 



The paper is illustrated by 84 heliotypes from photomi- 

 crographs. 



('83). STERNBERG, GEO. M. Photomicrographs and 

 how to make them ; pp. xv, 204, with twenty 

 plates of photomicrographs. James R. Os- 

 good & Co., Boston, 1883. 



('87). CROOKSHANK, EDGAR M. Photography of bac- 

 teria. Illustrated with 86 photographs re- 

 produced in autotype, pp. xix, 64, London, 

 H. K. Lewis, 1887. 



('87). Roux, E. La photographic appliance a 1'etude 

 des microbes. Ann. de 1'Inst. Pasteur, T. I, 

 1887, pp. 209-225. 



("88). ZETTNOW, E. Das Kupfer-Chrom-Filter. 

 Centralb. f. Bakt.. 1888. Bd. iv, pp. 51-52. 



This light filter is well adapted to photographing bac- 

 teria, whether they are stained red, blue or violet. 



This filter is made as follows: For use with sunlight, 

 160 grams copper nitrate and 14 grams pure chromic acid 

 diluted with water to 250 cc. More convenient to prepare 

 and suitable for most purposes in a layer l to 1 cm. thick 

 is 175 grams sulphate of copper and 17 grams bichromate 

 of potash dissolved in I litre of water. Thecopper-chrom- 

 filter transmits only a small portion of the spectrum , 

 viz., those yellow-green rays which act most strongly 

 upon erythrosin plates. For the concentrated solution 

 these rays are from wave length 580 to 560 : more diluted 

 from 590 to 545. 



