430 



SUBSTANCE 6V LEAVES. 



17. Rtf&dSE, wrinkled; when the veins of the leaves Contract 

 into a narrower compass than the disk, so that the substance be- 

 tween them is obliged to rise> as in Salvia. 



1 8. Concave, hollow ; when the margin of the leaf contracts^ 

 and becomes less than the circumscription of the disk, by which 

 means the disk is depressed. 



19. Venose, veiny; when the vessels are branched all over 

 the leaves, and their anastomose* or joinings are plain to the 

 naked eye. 



20. Nervose; when they have simple unbranched vessels, 

 that extend themselves from the base to the apex. 



21. Coloured ; when they change their green for some other 

 colour, as in Am ar an thus Tricolor^. 



22. Glabra, smooth; when the surface is void of all inequality, 



VII. The Substance of a leaf respects the conditions of its 

 sides : in this respect leaves are, ; 



1. TeretesJ, round, like a pillar; when they are for the 

 most part cylindric. 



2. Semi cylindric, like a halved cylinder; when they are 

 round on one side, and flat on the other. 



3. Tubulose, like a tube or pipe ; when upon cutting therri 

 they appear to be hollow within. 



4. Carnose, or succulent; when they are filled with a 

 pulp, 



* A term ivi anatomy, expressing the union of veins and arteries ; or wheffc they 

 pass from one branch to the other in smaller channels. Editor. 

 •f Three-coloured. 



X Round one way and long the other : our language has no distinct term to ex- 

 press roundness in this sense ; the figure is, by mathematicians, called a cylinder* 

 from a Greek word, signifying td roll j a body of this figure beirtg the best adapted 

 to that sqrt of motion. ( 



