284 The Rev. P. Keith on the Internal Structure of Plants. 



XL. On the Reappearance o/'Halley's Comet, 

 XT has generally been considered that this comet will not 

 A be seen till towards the end of the ensuing year 1835; and 

 the ephemerides of its place have been computed on this sup- 

 position. But Sir Thomas Brisbane has recently received a 

 letter from Mr. Rumker, who says that he thinks it may pos- 

 sibly be seen with a good telescope as early as December in 

 the present year ; and he has transmitted an ephemeris, com- 

 puted from the elements of M. Pontecoulant, which, through 

 the kindness of Sir Thomas Brisbane, we are here enabled to 

 present to our readers, and which, perhaps, may be the 

 means of detecting this singular and remarkable body nearly 

 a twelvemonth earlier than was expected. 



XLI. On the Internal Structure of Plants, By the Rev. 

 Patrick Keith, F,L.S, 



[Concluded from p. 188.] 



Elementary Organs. 

 QUCH is our analysis of the composite organs, from which 

 ^ it appears that they are all ultimately reducible either to 

 epidermoid lamina?, or to cells, or to longitudinal fibre ; which 

 we must consequently regard as being, under one modifica- 

 tion or other, the ultimate and elementary organs of the whole 

 fabric of the plant. Are the fibres of plants tubular? 



