402 APPLICATION OF METHODS OF BACTERIOLOGY 



tered through it. With a pointed forceps smear this carefully 

 upon two or three thin cover-slips, dry and fix them in the 

 way given for ordinary cover-slip preparations. Stain one 

 with Loffler's alkaline methylene-blue solution, another by 

 the Gram method, and a third after the method given for 

 bacterium tuberculosis in fluids or sputum. 



In that stained with Loffler's blue slip No. 1 will be 

 seen a great variety of organisms round cells, ovals, short 

 and long rods, perhaps spiral forms. But not infrequently 

 will be seen diplococci having more or less of a lancet shape, 

 joined together by their broad ends, the points of the lancet 

 being away from the point of juncture of the two cells. 

 There may also be seen masses of cocci which are conspicuous 

 by their arrangement into groups of fours, the adjacent 

 surfaces being somewhat flattened. 



In the slip stained by the Gram method the same groups 

 of cocci which grow as threes and fours will be seen; but 

 the lancet-shaped diplococci may now present an altered 

 appearance they are usually surrounded by a capsule. 

 This capsule is very delicate in structure, and, though a 

 frequent accompaniment, is not constant. It can sometimes 

 be demonstrated by the ordinary methods of staining, 

 though the method of Gram is most satisfactory. (Fig. 75.) 



In the third slip, which has been stained by the method 

 given for tubercle bacteria in sputum, if decolorization has 

 been properly conducted and no contrast-stain has been 

 employed, the field will be colorless or of only a very pale 

 rose color. None of the numerous organisms seen in the 

 first slip can now be detected; but instead there will be 

 seen scattered through the field very delicate, stained rods, 

 which present, in most instances, a conspicuous beading of 

 their protoplasm that is, the staining is not homogeneous, 



