\7i 



JUGLANDACE^. 



[part 



when the young plant begins to grow, it divides 

 into two cotyledons or seed-leaves, which drop 

 off when the true leaves are fully developed. 

 The kernel is covered with a thick skin, which 

 is very astringent ; and the nut is covered with a 

 membranaceous network of strong veins, which 

 are generally found in a withered state on opening 

 the ripe husk, having left their impression deeply 

 imprinted on the outside of the shell of the 

 walnut. The leaves are impari-pinnate, con- 

 sisting of four pairs of leaflets and a terminal 

 single one ; the lower pair of leaflets is much 

 the smallest, and the other leaflets are fre- 

 quently not opposite ; and they are sometimes 

 unequal at the base.- The main petiole is 

 dilated at the point where it joins the stem ; 

 and the leaves are placed alternately. The tree 

 is large and widely spreading; and the timber is 

 of a close grain, and takes a fine polish. 



The Black Walnut {J. nigra) differs from the 

 common kind, in the male 

 flowers being on a smaller and 

 more slender catkin, and fur- 

 nished with a brown roundish 

 bract at the back of the 

 calyx. The female flowers are 

 also in a sort of catkin, and 

 four or five together. The 

 fruit (see a in Jig. 78) is 

 round, and the husk verv thick 



Fk-. 78.— Leaf AND fruit 



OF THE Black Walnut 



(Juglans nigra). 



