28 OBJECT LESSONS IN BOTANY. 



33. It is also necessary to be acquainted with the vari- 

 ous forms of the apex of leaves. This diagram (Fig. 56) 

 will assist tlie memory. The apex may be acuminate^ end- 

 ing in a long, tapering point; or cusjpidate^ suddenly con- 

 tracted to a sharp, slender point; mucronate^ tipped with 

 a sj)iny point ; acute^ simply ending with an angle ; obtuse^ 

 blunt. 



34. Or the leaf may end without a point, being truncate^ 

 as if cut square off; retuse^ with a rounded and slightly de- 

 pressed end w^here the point should be ; emarginate^ having 

 a small notch at the end ; obcordate^ having a deep inden- 

 tation at the end. See also, and explain, the diagram of 

 the bases of leaves (Fig. 57). 



LESSON VII. 



COMPOUND LEAVES. 



35. A COMPOUND leaf consists of several distinct blades 

 borne on one petiole. (See Lesson Y., first paragraph.) 

 These separate blades are called leaflets. You notice that in 

 Fig. 39 each of the five leaflets has its own foot-stalk, called 

 petiolule^ and its own mid vein, &c. 



36. The Eose leaf (Fig. 58) is pinnately compound, or sim- 



33. Wliat does the term acuminate imply? What sort of apex is cuspi- 

 date ? mucronate ? acute ? obtuse ? 



34. Wlien may we call the apex truncate ? retuse ? emarginate V obcor 

 date ? Please name these several forms of the bases of leaves. 



35. Define a compound leaf. What is a leaflet ? What do you call the 

 foot-stalk of the leaflet ? 



