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VEGETABLE PHYSIOLOGY 



Drosera is a small plant which is found growing upon a 

 substratum of bog-moss (Sphagnum). Its dimensions are 

 small, the plant not being more than a few inches in height. 

 It bears a rosette of leaves, from the middle of which rises a 

 single scape of flowers, The leaves are covered with stalked 



FIG. 95. LEAF OF Drosera, SHOWING THE GLANDULAR TENTACLES. 



glands (fig. 95), which stand out from the surface. Each 

 gland has a somewhat substantial stalk, containing a rudi- 

 mentary vascular bundle. At the top of the stalk is a 

 rounded head which is always covered by a viscid secretion 

 that it pours out. Erom the shining appearance of the 

 glands with their drops of mucilage, the name of the plant, 

 Sundew, is derived. When an insect alights upon the leaf 

 it is entangled in the secretion, and, struggling to be free, is 



