THE ORIGIN OF LIFE 



27 



nucleus preceding that of the cell-body or cytoplasm. 

 Such a cell, consisting of nucleus and cytoplasm, is 

 the lowest unit of living matter, and all the supposed 



Fig. 5. A. Amoeba proteus. B. Euglena viridis. C. Paramecium 

 caudatum. D. A group of Bacteria. 1, Spirillum. 2, Bacillus. 

 3, Streptococcus. 4, Vibrio, n. nucleus, n'. micro-nucleus. 

 m. mouth, c.v. contractile vacuole. /. food vacuole. e. eye 

 spot. ch. chloroplastid. p. pyrenoid with starch concretion. 

 fl. flagellum. In C the small bodies in the cuticle represent 

 trichocysts, some of which are discharged in the anterior region. 



cases of living organisms in which a nucleus was 

 thought to be absent have been proved to be in- 

 correct. In the Bacteria (Fig. 5D), it is true, the 



