1891.] MICROSCOPICAL JOURNAL. 21 



Loeffler's second method in staining the flagelhx on both the typhoid 

 bacillus and the bacillus of ho": cholera. 



I have also found it to o^ive 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 by using the neutral or standard mordant (ii). I have found, 

 however, that the flagella on this bacillus stains quite as well by adding 

 from one to three drops of the acid solution to the mordant, which 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 undei'value these methods, 

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

 measure, successful. 



Bibliography. 



1. Cohu, F. Untersuchungen iiber Bacterien. Beitrdge zur Biologie tier Pfian- 



zen. Bd. I fiSyi), p. 127. 



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



Bacterium Termo. The Monthly Microscopical Journal (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. hoch. Robert. Untersuchungen iiber Bacterien. Beitriige zur Biologie der 



Pflanzen. Bd. II (1877), P- 416. 



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



Centralblatt f. Bakteriologie u. Parasiteiikunde. Bd. V (1889), p. Si. 



6. Loejfier, F. Ein neue Methode zum Fiirben 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. Trenkmann. Dr. Die Farbung der Geisseln von Spirillen und Bacillen. 



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



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



Ibid. Bd. VIII (1S90), p. 385. 



10. Doivdestvell, G. F. Note sur les Flagella der microbe der Cholera. An- 



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



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



Bakterien. Centralblatt f. Bakteriologie u. Parasitenkunde. Bd. 

 VIII (1890), p. 3S9. 



o 



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. Chccsetnan in The Micro- 

 scope., November., 1890. 



o 



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. 



