2 JOURNAL OF THE [January, 



between two covers, afterward drawn apart ; the completion of 

 the drying of the fihn on the cover by passing it to and fro 

 through a flame ; and the staining in simple solutions of anilin 

 colors in water, anilin-water, or alcohol. No worker should any 

 longer waste his time and labor on such a process, with its known 

 miserable results in imperfect mounts and the unsatisfactory con- 

 clusions they must yield. 



1. The material is spread irregularly. On account of its ordi- 

 nary glutinous character and excessive richness in forms, the film 

 on most bacteria mounts is either rendered too dense, crowded, 

 and opaque, or, at the other extreme, is represented by a few 

 scanty wisps or streaks, for which a tedious search must be made 

 all over the cover. 



2. The true structure and grouping of the bacteria are dis- 

 turbed or destroyed. In the rough process of smearing, the deli- 

 cate attachment of the elements of bacterial filaments and of 

 groups of cocci, often loosely aggregated, is rudely broken up. 

 In place of bacterial chains, the student often obtains a film, 

 partly or wholly consisting of desiccated and widely scattered 

 bacilli ; in place of streptococci, groups of four, grape-like 

 bunches and cubical packets, he finds solitary cocci and perhaps^ 

 a few lonely diplococci ; and, very likely, his original spirilla and 

 even vibrios have been nearly all rent apart into isolated curved 

 bacilli ; there is now a question whether some of the so-called 

 spirochaete may not be but the paddles torn away from the bodies 

 of roughly handled hsematozoa. 



As the discrimination of bacterial species, still very difficult, 

 depends partly, often largely, on recognition of original forms and 

 grouping, the present destructive and clumsy process of smearing 

 has often long delayed the detection of important facts {e.g., the 

 spirillum form of the organism connected with Asiatic cholera) 

 and ought to be entirely rejected. For these reasons several 

 writers have recently recommended the previous dilution of the 

 original bacterial growth with sterilized water upon the cover, or 

 before its application to the cover. In fact, we have had one 

 truthful process, in preservation of bacterial forms, that of 

 cover-impressions from the surface of solid and liquid media ; but 

 these have been of limited and often difficult application. 



3. Further distortions of form occur during the processes of 



