SOLID CULTIVATION MEDIA. 



wire is now withdrawn, and the cotton wool plug is firmly replaced in 

 the mouth of the test-tube. All these manipulations must be carried 



Fig. 34. — Method of inoculation in test-tubes containing nutrient 

 jelly. 



a. Cultivation in jelly, from which inoculation is to he made. 



b. Tube containing sterile jelly, into which the straight needle is 



introduced. 



c. Cotton wadding plugs held between the tips of the fingers. 



(The hand is held in such a position that these plugs have 

 their smooth surfaces downwards.) 



out in a perfectly still atmosphere, or under the protection of the 

 carbolic spray. The latter method specially offers many advantages : 



