1 66 THE TEACHING BOTANIST 



life and development of the seed must be briefly described to 

 them with reference to the use of each part. This applies in 

 particular to the markings ; the use of parts of the embryo 

 they will learn for themselves later. Along with this, and after 

 making them feel the need for single terms to describe the 

 different features, the proper names may be given them for 

 the parts, and these terms may be the better impressed upon 

 them if accompanied by side remarks upon their etymology, 

 etc. Of course names and uses should be carefully recorded. 

 Terms needed are Coats, Hilum, Micropyle (Strophiole, very 

 small in bean), Raphe, Chalaza, Embryo, Cotyledons, Hypo- 



,..blurnule 

 SCQTO/ cotyledon 



-c.au title 



co.ttj/edons 



FIG. 14. Good drawing, by a beginner, of embryo of Lima Bean laid open. 



Actual size. 



cotyl (or Caulicle), Plumule. (Of course the chalaza itself does 

 not appear in the seed, but its position is shown by a slight 

 projection or angle, which may be called the " chalazal angle.") 

 The names may be added as shown in Figs. 12, 13, 14. 



The teacher will do well to work up for himself the develop- 

 ment of the ovule in the Bean, which can very easily be done 

 from String Beans of different sizes. By a series of outline 

 diagrams he can then make clear to the class the exact mean- 

 ing of the peculiarities of form and markings in the seed. This 

 would form an excellent topic for investigation by some of the 

 brightest pupils. 



