4l6 Mr. Bowman on the Parasitical Connection 



which the bladders float, to minister to the support of the 

 plant during the decay of the old and the formation of the new 

 tubers. The scaly roots of Lilittm candiclum and the tunicate 

 ones of Narcissus are provided with similar bladders in their cel- 

 lular substance, which also are detached and sink in water. In 

 the former they are smaller and more numerous than in La- 

 thraa ; and those in the upper portions of the scales are chiefly 

 concentrated round the fascicles of spiral. sap- vessels. It is 

 worthy of remark, that the cuticle of these scales has also no 

 absorbents, nor do they become green by long exposure to 

 light. 



I have already hinted, that the partial shade in which the 

 Lalhrcea is always found cannot be the sole cause of its pale 

 and sickly colour. Many other plants, which grow promiscu- 

 ously with it, flourish, and severally possess their full and pecu- 

 liar tints of green*. These all draw their nourishment imme- 

 diately from the soil ; have leaves furnished with cuticular pores, 

 and are powerfully attracted by light. Not so our Lathraa ; for 

 when its flower-stems have acquired their full altitude, they are 

 always perpendicular ; and in groups of twenty or thirty in the 

 most umbrageous situations, the rows of flowers (which have 

 always an unilateral direction) are as frequently turned from 

 the only side on which light is admitted as towards it. J have 

 repeatedly witnessed this singular fact ; and have even seen it 

 come up within, though near the door of, a dark hovel, without 

 the stem or its flowers evincing any tendency to incline towards 

 the light. Again, it will be recollected that the various species 

 of Orobanche and Cuscuta show no inclination to put on the 

 usual vegetable robe of green, though not hidden " from day's 

 garish eye." It is therefore, I conceive, in the structure and 



* Such as Melica uniftora, Samcula europcea, Allium ursirium, Scilla nutam, 

 Geranium Robeitianum, &c. &c. 



mode 



