Slime Moulds, Bacteria, and Yeasts. 257 



to determine the details of their construction. They are 

 enveloped by an extremely thin translucent membrane. 

 Whether they have nuclei is a question which is still in 





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4y ,v:> «-'.;;;^i;r-' 





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f0 ^A*--i/s'„»*l.& 





c Fig. 133. d 



fz, yeast plants, some of them budding; d, micrococci (singular, micrococcus) from 

 the air; c, Bacillus subtilis, showing internal spore-formation ; d, bacilli (singu- 

 lar, bacillus) of Asiatic cholera, with motile flagella. Photomicrographs X 740. 

 After GiJNTHER. 



doubt. It is thought by some that the bulk of their bodies 

 is made up of nuclear material. 



153. Methods of Reproduction. — Bacteria reproduce by 

 division, one becoming two, two four, and so on. Asexual 

 spores are also formed, either by the ordinary cells pro- 



