BACTERIA. 81 



by partition and formation of viscous matter form zoogloea ; 

 these cocci frequently grow to articulate filaments, which are 

 provided with distinct sheaths (h, i r) ; they increase in 

 thickness towards the apex ; when they have arrived at a certain 

 age, they divide within the sheath into smaller pieces, which 

 become round and issue forth as rods, macro- or micrococci ; 

 these are sometimes seen floating about in water. We do 

 not yet possess a more exact knowledge of the life-history 

 of this beautiful bacterium. 



