SPORES 



47 



(Fig. 30). In a few forms the spore is placed at the end of 

 the rod and shows a marked enlargement. This is spoken 

 of as the " plectridium" or more commonly the "drumstick 

 spore" (Fig. 31). The position and shape of the spore are 



Fig. 29. — Spores at the end of the 

 rod with no enlargement of the rod 

 around them. The Hghter areas in 

 the rods are spores. 



Fig. 30. — Spores at the end of the 

 rod with enlargement of the rod, 

 A, A, A, A. 



constant for each kind of bacteria. In one or two instances 



only, two spores have been observed in a single organism. 



; : ■ iiat the protoplasm is denser and the spore capr 



' - (the percentage of water in each is decidedly 



Fig. 31. — Drumstick spores at the end of the rod. 



less than in the growing cell) gives the spore the property 

 of much greater resistance to all destructive agencies than 

 the active bacterium has. For example, all actively growing 

 cells are destroyed by boiling in a very few minutes, while 



