1891.] MICROSCOPICAL JOURNAL. 21 



Loeffler's second method in staining the flagella on both the typlioid 

 bacillus and the bacillus of hog cholera. 



I have also found it to give the best results in staining the flagella on 

 a considerable number of motile bacteria. Although the bacillus of 

 hog cholera is an alkali-producing organism, Dr. Smith stained its 

 flagella b.y using the neutral or standard mordant (ii). I have found, 

 hovs^ever, that the flagella on this bacillus stains quite as w^ell by adding 

 from one to three drops of the acid solution to the mordant, w^hich shows 

 that the range in the reaction of the mordant that can be used in stain- 

 ing the flagella, on this germ at least, is much greater than might be 

 inferred from the method. This is of considerable importance, as it 

 will, if true with respect to all germs, greatly diminish the number of 

 test experiments in order to determine the degree of the reaction of the 

 mordant necessary to be used with the germ in question. With Trenk- 

 mann's second process I have been partially successful, but with the 

 other methods I have met with only negative results. Thus far, how- 

 ever, my experience has been too limited to undervalue these methods, 

 or to recommend too highly the one with which I have been, in a 

 measure, successful. 



Bibliography. 



1. Cohn, F. Untersuchungen iiber Bacterien. Beitrdge zur Biologic der PJiati- 



ze7i. Bd. I (1872), p. 127. 



2. Dallinger^ W. H., and Drysdale, J. J. On the existence of Flagella in 



Bacterium Termo. The Monthly Microscopical Jouy-nal (London). 

 Vol. xiv (1875), P- 105- 



3. Dallinger, W. H. On the Measurement of the Diameter of the Flagella 



of Bacterium Termo. Jour, of the Royal Mic. Society. Vol. i (1878), 

 p. 169. 



4. Koch, Robert. Untersuchungen iiber Bacterien. Beitriige zur Biologic der 



PJlanzen. Bd. II (1877), P- 4i6. 



5. JVeuhauss, R. Ueber die Gisselen an den Bacillen der Asiatischen Cholera. 



Centralblatt f. Bakteriologie 11. Parasitenkuiide. Bd. V (1889), P- Si. 



6. Loeffler, F. Ein neue Methode zum Farben der Mikro-organismen im be- 



sonderen ihren Wimperhare und Geisseln. Ibid. Bd. VI (1889), p. 209. 



7. Loeffler, F. Weitere Untersuchungen iiber die Beizung und Farbung der 



Geisseln bei den Bakterien. Ibid. Bd. VII (1890), p. 625. 



8. Trcjikmann, Dr. Die Farbung der Geisseln von Spirillen und Bacillen. 



Ibid. Bd. VI (1889), p. 433. 



9. Tre7iknia7in, Dr. Die Farbung der Geisseln von Spirillen und Bacillen. 



Ibid. Bd. VIII (1890), p. 385. 



10. Dowdeszvell, G. F. Note sur les Flagella der microbe der Cholera. Ati- 



nales de Micrographie. T. II (1890), p. 367. 



11. Smith, Theobald. Einige Bemerkungen iiber Saure-und Alkalibildung bei 



Bakterien. Centralblatt f. Bakteriologie u. Parasitenkuiide. Bd. 

 VIII (1890), p. 389. 



Cleaning Slides. — If spoiled in mounting, I use a saturated solution 

 of borax in water, in which I soak the slides for a few days, then rinse 

 in clean water. Borax is a solvent for balsam, shellac, and other cements 

 used in mounting, and does not act on the glass like soda, which is often 

 recommended for this purpose. — E. L. Cheeseman hi The Micro- 

 scope., November., i8go. 



Compound Eyes. — The development of the compound eyes of 

 Arthropods is discussed by Mr. S. Watase (Johns Hop. Biol. Studies, 

 iv, 387) with the conclusion that they are the result of an ectodermal 

 invagination essentially similar to that of the single eye. 



