14} PLANARIA FLEXILIS. 



of the food alone, and its subsequent assi- 

 milation with the substance of the plana- 

 riae. The peculiar colour impressed on 

 the observer, was from at first sight con- 

 founding the infinite ramifications with the 

 general mass of the body : the size had 

 been affected by a copious supply of ali- 

 ment ; and as motion is accelerated or re- 

 laxed by the pressure of necessity and ex- 

 ternal temperature united, some unusual 

 combination had operated here. Along 

 with the disappearance of the food, the co- 

 lour vanished ; the size was, from the same 

 cause, reduced to its accustomed limits : 

 hunger stimulated to action ; and animals, 

 identically such as I was wont to behold, 

 were before me. This is a cogent illustra- 

 tion of the advantage of leisurely awaiting 

 the alteration which may be undergone by 

 beings so susceptible of change. All the 

 planariae that have come under my inspec- 

 tion, would seem, to a superficial observer, 

 quite different species in a state of absti- 

 nence from what they are in a state of re- 



