GREAT STEPS IN EVOLUTION 85 



unicellular st.fl.-te; jjlfy (j|o not. formA'Jbtuiigg " 



Her** w^ ^^v^ p^^^pp t^^ g^nt^st gap and 



the gr^,fp g t g *T i" nrgfl.nfc pfy^^tVmJh 

 bff.tWfifi 1 ^ ainglfv-rallftd- a.nd ]T]fl;py-celled organ- 

 isms. It is very interesting to inquire into 

 the beginning of a " body." What are the 

 possibilities? 



We know of some simple units that have a 

 habit of coalescing into composite masses, of I 

 others in which the nucleus divides over and 

 over again within the cell so thflj^ pmiltj-'B. 

 rnip.]fifl.t.f> orgfl.n^srflff ftre formed, and of others 

 again that break their definition, and do their 

 best to get beyond the unicellular state, by 

 forming loose colonies. It was prnfrafrly in 

 fTip.sp~wa.ys thnt body-making 



began. Certain simple organisms, unable 

 fully to complete that division into two or 

 more separate units which normally occurs 

 at the limit of growth, bridged what Agassiz 

 called "the greatest gulf in organic nature." 

 It was perhaps through some weakness that 

 the daughter-units, formed by division of 

 the mother-cell, remained associated, instead 

 of drifting apart in individual completeness, 

 But out of this weakness if weakness 

 strength arose, the strength of animals 

 with a body. 



BEGINNING OF DEATH. In a startling 

 phrase the immortality of the Protozoa 



