HOUSEHOLD BACTERIOLOGY. 



Food of 

 Bacteria 



Reproduction 

 of Bacteria 



gans like higher plants. They are simply transpar- 

 ent bits of jelly-like protoplasm. 



Bacteria in general like the same kinds of food that 

 man likes, although they do not require the variety 

 in diet which to civilized man seems necessary. 



Some flourish best in 

 meat juices, others in 

 milk, some in starchy 

 foods, others in su- 

 gary solutions, while 

 still others enjoy best 



Fig. 11. Different Forms of Bacilli. the fats. 



(a) Simple, detaened forms. 



(b) Chains of united bacilli. They algo show> j ike 



man, a surprising faculty of adaptation. If unable to 

 get their favorite food, many will grow on whatever is 

 at hand. Any organic substance which is not absolutely 

 dry may become food for some species of dust-plants. 

 Dust-plants will not leave the moist surfaces upon 

 which they fall, but where such surfaces become dry, 

 then the plants are ready to be blown into the air by 

 winds or carried along on anything which touches 

 them. 



Ordinarily dust particles are probably never so dry 

 that the bacteria or other micro-organisms clinging to 

 them are killed. 



All bacteria reproduce by division of the parent 

 into halves, which process is called fission. Fig. 10. 

 Sometimes these daughter cells remain attached even 

 after they themselves have divided into two. A 



