52 



THE BIOLOGICAL PROBLEM OF TO-DA Y 



produced. Thus, artificially, an animal with two 

 mouth-openings or two heads was produced; and, 



FIG. 1. CERIANTHUS MEMBEANACEUS, in which a second oral 

 aperture, surrounded by tentacles, has appeared as the result of 

 an artificial slit. (After Locb.) 



FIG. 2. CIOXE INTESTINAL:*, in which eye-specks resembling 

 those surrounding the mouth have appeared in the neighbour- 

 hood of an artificial opening () 



/ 



similarly, animals with a row of three or more 

 heads may be produced. 



