128 



MORPHOLOGY AND CULTURE OF MICROORGANISMS 



tending along the surface of the organisms or special organs for the 

 intake of food. 



REPRODUCTION 



The protozoa reproduce in many different ways and several of these 

 ways may occur in a single organism. For this reason, their repro- 

 ductive power is very great; in power of repeating their like, they fall 

 just short of the bacteria. The union of a male and a female form does 



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^ . -. : 



$ :. 5 v. .' 



- :: ' : J..A- '' - \ 



^SS^^P 



FIG. 93. Stages in the division of Amoeba poly podia. (After F. E. Schulze and Lange 



from Doflein.} 



not always precede multiplication; sexual union and reproduction, 

 though now combined in many animals, may have been originally two 

 entirely distinct phenomena and, in the protozoa, though sexual union 

 may be concerned with the production of new individuals, it is often 

 especially associated with the regeneration of the protoplasm of the 

 parasites taking part in it. 



The simplest of the methods of reproduction is simple binary divi- 

 sion, in which the organism divides into two equal parts. A modifica- 

 tion of this process is gemmulation, in which a small protozoon buds off 



