1KI.1 \< I. 



is overcome. Hut it is liardly necessan to tit in natural 



history many facts which have been originally ii. by 



minute and laborious research, air subsequently ascertained t.. 

 connected with other facts of a more obvious nature; and of tl 

 B itany offers perhaps tin- must striking proof that can be adduced. 

 One of the first questions to be determined b_v a student of Botanj . 

 who wishes to inform himself <»t' the name, affinities, and us 

 of a plant, seems to l)c, whether it contains spiral \< r not, 



because some of the great divisions of the vegetable kingdom i 

 characterised by the presence or absence of those minul a as. 

 I- ■ tene that careful observation, and multiplied microscopical 

 analyses, have taught Botanists that certain plants have spiral 



—els, and others have none; hut it is not true, that in practice 



minute and difficult an inquiry needs to be instituted, because it 

 has also been ascertained that plants which bear flowers have spiral 

 vessels, and that such as have no flowers are usually destitute of 



ral vessels, properly so called; so that the inquiry of the student, 

 instead of being directed in the first instance to an obscure but 

 highly curious microscopical fact, is at once 1 arrested by the tv\u 

 most obvious peculiarities of the vegetable kingdom. 



Then, again, among flowering plants two great divisions have 

 been formed, the names of which. Mouucotvledons and Dicotyle- 

 dons, are derived from the former having usually but one lobe to 

 the Beed, and the latter two, — a structure much more difficult to 

 ascertain than the presence or absence of spiral vessi s. Hut no 

 Botanist would proceed to dissect the seeds of a plant for the pur- 

 pose of determining to which of those divisions it belongs, except 

 in some very special case, lie knows from experience that the 

 minute organisation of the seed corresponds with a peculiar structure 



of the stem. Leaves, and flowers, the most highly developed, and 1 1 1 • s1 



3 ly examined parts of vegetation; a Botanist, therefore, prefl - 

 to examine the stem, the flower, or the leaf of a plant, in order 

 to determine whether it is a Monocotyledon or a Dicotyledon, and 



rarely finds it necessary to anatomise the seed. 



'flic presence or absence of albumen, the structure of theembr 



th<> position ,,t' the m eds or ov ulcs, the nature ofthe fruit, tin- modi- 

 fications of the flower, are not to be brought forward as other 

 difficult points peculiar to the study of tin Na1 Sysl m, 



because, whatever system is followed, the student must make him- 

 self acquainted with such facts, tor the purpose of determining 

 genera. The common Toad-flax cannot be discovered bv 



