152 



LIFE ON THE FARM. 



but these species are not so numerous as the harm- 

 less kinds. 



BACILLUS SUBT1LIS IN HAY INFUSION. 



a, short rod ; b, non-motile rods and chains ; c, spores ; d, motile 

 chains; e t mass of spores forming a pellicle. 



FORMS AND GROWTH. 



Though they are very small, yet bacteria have 

 definite shapes. Some kinds are spherical, some 

 cylindrical, and some spiral. These three general 



