40 FIRST STEPS IN GENERAL KNOWLEDGE. 



pie and easy mark of these different manners of 

 growth. 



"The plants that increase within," he said, 

 "have the veins of their leaves in straight lines 

 from one end of the leaf to the other, and those 

 that increase without have a beautiful network 

 of veins all over the leaf. If you collect a few 

 leaves from the garden, you will soon see the 

 difference." 



The children' ran into the flower-garden and 

 gathered such early leaves as they could find ; and 

 bringing them to their father, he held up to the 

 light a crocus and a hyacinth leaf, and showed 

 them how beautifully regular are the parallel 

 veins running from end to end. 



"This shows that crocuses and hyacinths are 

 endogens," he said; "but if you look at these 

 lilac and ivy, and primrose and violet leaves, you 

 see at' a glance that the veins branch out from the 

 rib which runs down the middle of the leaf, and 

 then subdivide into a kind of network ; therefore 

 these leaves belong to exogens." 



" Oh yes, papa," said Mary, " and that is what 

 makes skeleton-leaves so pretty. How very easy 

 it will be to find out which are endogens and 



