THE EARLIEST KNOWN FORMS OF LIFE 

 ON THE GLOBE, 



BY 



C. CALLAWAY, M.A., D.Sc, F.G.S. 



(Read March 21st, 1899) 



Our Hon. Secretary, in a paper read before the Club 

 on January 24th, called attention to a very recent 

 phase of the process of evolution. He described some of 

 the evidence which leads to the belief that Man is derived 

 from the lower animals. He sketched the probable hne 

 of descent from the Ascidian or Sea-squirt. But the 

 Ascidian is itself an animal of some complexity of 

 organisation, possessing distinct organs of respiration and 

 circulation, and being furnished with a granule of nervous 

 matter, answering the purpose of a brain. When the 

 Ascidian first came into being we probably shall never 

 know, for the tissue of the animal is entirely perishable, 

 and it is hardly likely that its sac-like body has left any 

 traces of itself in the earth's crust. It seems, however, 

 fairly certain that this ancestor of our race flourished in 

 Pre-Cambrian times, for the lowest Cambrian strata 

 contain the remains of several animal types of much 

 higher organisation. This leads me to the main topic of 

 my paper. 



F 



