58 



CLASSIFICATION^ 



Fig. 52. — Illustrates the genus 

 Pseudomonas. A bacillus with flag- 

 ella at the eud only. 



Fig. 53. — Illustrates the genus 

 Microspira. It is (though the 

 photograph does not prove it) a 

 short spiral with one flagelluin at 

 the end. 



Fig. 54. — Illustrates the genus 

 Spirillum. Spiral bacteria with 

 more than three, in this case four, 

 flagella at the end. 



Fig, 



^Illustrates the genus 

 Spirochseta. 



Fig. 56. — Illustrates the genus 

 Chlamydothrix. Fine threads with a 

 delicate sheath. 



Fig, 57t — Illustrates the genus 

 CrenothriX. The thickness of the 

 cell walls is due to deposits of iron 

 hydroxide. (After Lafar.) 



