33« THE AMERICAN MONTHLY [Dec, 



A8 a result of tlie experiments the following facts were estab- 

 lished. 



1. No /r/'fearbon was anywhere present. 



2. All carbon was contained in leucocytes and true spleen- 

 pulp cells. 



3. Ingested cells were free on mucous and epidermic surfaces. 



4. Ingested cells wore in excretory organs with waste pro- 

 ducts. 



From these facts it may be concluded that leucocytes are lost 

 from the body in 3 ways : by wandering out on mucous and epi- 

 dermic surfaces; by jtiissing away with waste products ; by in- 

 gestion, by splenic cells. Since the ;mimals ex})erimented upon 

 were kept in normal conditions and, so far as known, no patho- 

 logical conditions subsequently supervened, this loss can be con- 

 sidered as a usual occurrence. The removal of the carbon in 

 this way suggests the method of the removal of any foreign ma- 

 terial of a like or even of a dissimilar nature that may chance to 

 come into the circulation of the animal. Thus the leucocytes 

 truly become the scavengers of the body. 



To Mount Certain Salts. 



By NO SIG. 

 PAKIS. 



{Continued from page 261.) 



II. TO CLEAR SPOILED SLIDES. 



Before describing the manner of making a preparation of the 

 next salt it will be as well to give the best way of cleaning off 

 the sjtoilt slides and getting them in a fit state to use again, as 

 you will find that there is sure to be a great many spoilt in 

 iheir preparation at the different stages, and as it is not worth 

 while to preserve any but pretty perfe6t specimens, it is better 

 to get them cleaned off as soon as possible to prevent accumu- 

 lation. 



If the slide, after warming does not give a characteristic and 

 good specimen of crystals, the salt should be scraped off with a 

 blunt pocket knife and placed in a flatdish under water at once. 

 Many salts, if left for long on the glass, seem to eat into the sur- 

 face and show the shape of the deposit when you breath on 

 the glass, even after having been thoroughly cleaned. Where 



