306 VEGETABLE ORGANOGRAPHY. 



a certain quantity of sap ; but it appears, however, that, 

 at least in the young state of the plant, it is absolutely 

 necessary that the Orohanche should be attached to a 

 plant provided with leaves. It is most probable that 

 Lathrcea, Monotropa Orchis ahoriiva, and Limodorum 

 epipogium, are nourished in an analogous manner ; but 

 the nutrition of these singular plants has been but Kttle 

 studied, and it is desirable that their history should be 

 followed in detail and with accuracy by some botanist 

 accustomed to physiological observations. 



CHAPTER IV. 



OF THE NUTRITIVE ORGANS OF CELLULAR PLANTS. 



Section I. 

 General Considerations. 



After having described the numberless variations, 

 but which are subject to general rules, which the nu- 

 tritive organs of vascular plants present, it is necessary 

 to speak of the organs which correspond to them in 

 cellular plants. Here we shall find as much similarity 

 in the inner parts as we have remarked differences in 

 vascular plants, and the external forms are here in pro- 

 portion more varied than in the large plants. 



Cellular plants have not, as we have already m.entioned, 

 either vessels, properly so called, or storaata: the former 

 appear to be replaced, as regards their office, and often 



