204 BACTERIOLOGY. 



involution-forms or other variations in morphology. 

 Grouping, as in pairs, chains, clumps, zooglcea; pres- 

 ence of capsule; development and germination of spores; 

 arrangement of flagella. 



3. Staining-peculiarities — especially its reactions with 

 Gram's (or Weigert's fibrin) stain, and peculiar or irreg- 

 ular modes of staining. 



4. Motility — to be determined on very fresh cultures 

 and on cultures in different media. 



5. Its relation to oxygen — is it aerobic, anaerobic, 

 or facultative ? Does it develop in other gases, as car- 

 bonic acid, hydrogen, etc. ? 



6. Both the macroscopic and microscopic appearance 

 of its colonies on nutrient gelatin and on nutrient agar- 

 agar. 



7. The appearance of its growth in stab- and slant- 

 cultures on gelatin, agar-agar, blood-serum, and on 

 potato. 



8. The character of its growth in fluid media, as in 

 bouillon, milk, litmus milk, rosolic-acid-peptone solu- 

 tion, and in bouillon containing glucose. 



9. Does it grow best in acid, alkaline, or neutral 

 media ? 



10. Is the normal reaction of the medium altered by 

 its growth ? Is its growth accompanied by the produc- 

 tion of indol; is the indol associated with the coincident 

 production of nitrites? 



11. Is its growth accompanied by the production of 

 gas, as evidenced by the appearance of gas-bubbles in 

 the media— both in media containing fermentable sugars 

 and those from which these bodies are absent? "When 

 cultivated in sugar-bouillon in the fermentation-tube, 

 what production of gas is evolved under known condi- 



