PLANARIA FELINA. 47 



planariae, within a tall glass jar. Their nu- 

 merous descents from the upper leaves, 

 quickly form a perceptible column, owing 

 to the infinity of glutinous or silken lines. 

 The animal being extremely sensible of 

 cold, a considerable temperature is requi- 

 red to promote its activity. On the se- 

 venth of August 1812, though the thermo- 

 meter in the heat of the day stood at 62, a 

 certain chilness from a breeze at east per- 

 vaded the air, which led planariae to retreat 

 under stones for shelter. 



The mucilaginous part of decaying ve- 

 getables probably constitutes the ordinary 

 food of this species ; but animal substances 

 are also voraciously consumed, especially 

 the soft and bloody portions. Mussels and 

 oysters are peculiarly grateful ; and after 

 feeding copiously, the whole body of the 

 planaria rises from a flattened form almost 

 into a semi-cylindrical shape. In this con- 

 dition, its various proportions are best ex- 

 posed, in consequence of the universal or- 

 ganization being expanded. Sometimes, 



