Fig. 133.—From the thinnest part of plate 2, [Fig. 131] as seen under the low-power objective. × 100. Colonies much larger than on plate 1, but still crowded.

Fig. 134.—The smallest colony on plate 3, [Fig. 131], as seen under the low-power objective. × 100. Large, single, isolated colony.

Professor W. A. Starin of the author’s department, a former student of Professor Barber, has done some excellent work with this apparatus.

Fig. 135.—Diagram of Barber’s isolation apparatus. b, moist chamber; ms, large cover-glass over moist chamber; p, small pipette drawn out to a fine point; k, r, g, pipette holder; f, screw for raising and lowering k, r, g; s, screw for lateral motion of k, r, g; n, screw for clamp on pipette which allows it to be moved in or out; m, mechanical stage of microscope; t, rubber tube held in the mouth and used to move the liquid culture medium in the pipette. (Journal of Infectious Diseases, October 20, 1908, vol. 5, No. 4, p. 381.)

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Fig. 136.—Photograph of microscope with Barber’s isolation apparatus set up to use.