162 BACTERIOLOGY. 



affect urea? Prepare an outline, as with the last species, and make 

 drawings of cultures and cells. 



Laboratory exercise No. 5Q.8arcina luted. Expose agar-agar in a 

 Petri dish to the air, and from the j^ellowish colonies which develop 

 prepare plates. Inoculate tubes (from the pure cultures thus obtained) 

 of agar and gelatin. Describe the growth in each tube. Stain by 

 method No. 10. Note the cocci, arranged singly, in pairs, in tetrads, 

 and in packets. Make drawings of cultures and cells. 



Laboratory exercise No. 57. Spirillum rubrum. Obtain a pure culture 

 of this species. Prepare a cover-glass spread, and stain with gentian- 

 violet, method No. 10. Note the spirals and count the turns in each. 

 Drawings. 



Note. Other species may be substituted for those given above, and 

 additional ones may be required. 



MEMORANDA. 



