117 

 MONDAY AFTERNOON POPULAR LECTURES. 



ZOOLOGY. 



IDEAS ON THE BEGINNING OF LIFE. 

 By J. Ballantyne. 



{Read February 10, 1890.) 



Organic life, as you all know, is arranged by naturalists into two 

 great divisions, named respectively the vegetable and animal king- 

 doms, the last named of which being the subject matter of this paper. 



To the ordinary observer the difference between plants and animals 

 can be seen at once, as only the higher or more specialised forms are 

 compared, but with the naturalist, who digs down into the lower forms 

 of life, distinctions all but disappear, so that he finds it impossible to 

 fix the point where the diverging lines of life really begin, or to say 

 whether vegetable or animal life had precedence in the order of their 

 beginning in the far distant past* Dr. Andrew Wilson, of Edinburgh, 

 in his work " Chapters on Evolution," says : " In the lowest deeps of 

 plant life we may discover organisms which possess at the best a doubt- 

 ful title to be regarded as objects of botanical study. In the animal 

 world, likewise, are included lower organisms which may be regarded 

 in certain aspects as possessing true relationship with plants. Modern 

 biology to-day frankly admits its inability to pronounce whether certain 

 lowest forms of life are animals or plants, certain ' monads,' for example, 

 consisting each of a speck of protoplasm provided with microscopic 

 whip-tails, exhibit a highly confusing idtntity of structure and function 

 which renders their exact nature indeterminable, or at least highly 

 doubtful. Hence we discover that apparently at the lowest confines of 

 the animal and plant realms, we enter a biological ' no man's land/ 

 whereof the included inhabitants may legitimately claim relationship 

 with both kingdoms. They exhibit in this latter respect, in the eyes 

 of biologists, the actual survivals of that early epoch in the history of 

 life's development when the specialized kingdoms of animals and plants 

 were not, and when existence passed placidly along the common lines 

 which were soon to diverge into two great series--©f Jiving beings that 

 environ our footsteps to-day." v \ 



UJ 



