QUERCUS. 



209 



But in ripening, only 1 of the 6 ovules becomes a seed. By 

 its fruit the acorn, the Oaks are universally known. It is, 

 by suppression, a 1-seeded nut partly immersed 

 in a scaly, cup-form involucre. On dissection, 

 we find in the seed an embryo with 2 massive 

 cotyledons, the short radicle pointing upward, 

 destitute of albumen. 



Germination. Under the Oaks at the time 

 of flowering, the student will find acorns of the 

 preceding year in all stages of germination as 

 shown in the cuts. The swelled co- 

 tyledons (which are but transformed 

 leaves) cannot extricate themselves 

 from the shell, but burst it and thrust 

 forth their petioles with the radicle 

 and plumule between them, the 

 former to grow downward, the 

 latter upward. 



The Name of this noble 

 genus is the classic Latin 

 one Quercus. * In the 

 United States there grow 

 as many as 25 species, and 

 at least 6 or 8 in every 

 vicinity. The practiced 

 eye will distin- 

 guish them by their 

 tree-forms alone. All 

 may know them by 

 the forms of their 

 leaves (Appendix). To identify them by verbal description is 



Acorn (seed of Quercvs palus- 

 tris) germinating: 6,section show- 

 ing the radicle (r) which is to be- 

 come the root, and the two cotyledons (c) which are 

 to nourish it; 7, the radicle r, descending; 8 and 9, the 

 radicle r, descending, and the plumule ( p) ascending. 



* The Oak has been identified with man's history from the earliest ages. Its groves 

 nave been held sacred alike by Jews (Gen. xxi, 33), Greeks, Romans and Celts. The 



