or REVERSED PLANTS. Qt 



no agsiregation of woody circles ; and yet in some oi' 

 this tribe the spurious kind of stem, formed in the man- 

 ner just described, when cut across shows something of 

 a circular arrangement of fibres, arising from the origi- 

 nal disposition of the leaves. The common orange lily, 

 Lilium bulhiferum^ Curt. Mag. t. 36, and white lily, 

 X. candidum, t. 278, which belong to the same natural 

 family called monocotyledones^ serve to elucidate this 

 subject. Their stems, though of only annual duration, 

 are formed nearly on the same principle as that of a Palm, 

 and are really congeries of leaves rising one above an- 

 other, and united by their bases into an apparent stem. 

 In these the spiral coats of the sap- vessels are very easily 

 discernible. 



To conclude this subject of the propulsion of the sap, 

 it is necessary to say a few words on the power which 

 the vessels of plants are reported to possess of convey- 

 ing their appropriate fluids equally well in either direc- 

 tion ; or, in other words, that it is indifferent whether 

 a cutting of any kind be planted with its upper or lower 

 end in the ground. On this subject also Mr. Knight 

 has aftbrded us new information, by observing that, in 

 cuttings so treated, the returning vessels retain so much 

 of their original nature as to deposit new wood above 

 the leaf-buds ; that is, in the part of the cutting which, 

 if planted in its natural position, would have been below 

 them. It appears, however, that the sap-vessels must 

 absorb and transmit their sap in a direction contrary to 

 what is natural ; and it is highly probable, that, after 

 some revolving seasons, new returning vessels would be 

 formed in that part of the gtem which is now below the 



