248 



terior consists of two halves, connected at one point by a 

 short sprout-like body. Between these two halves, es- 

 pecially in seeds that have commenced to swell, we can see 

 even with the unaided eye, the young shoot that is des- 

 tined to become the new plant. These two halves of the 

 seed contain a rich supply of nourishment, and as the seed 

 sprouts, they become the first leaves of the young plants 

 and supply its food until it has developed its roots and is 

 able to obtain nourishment from the soil. This structure 

 which forms the entire contents of the hull in the cases 

 mentioned, is called an embryo, as it is really nothing but a 

 young plant. It is the possession of this embryo that dis- 

 tinguishes a seed as such. In other seeds like the morning 

 glory and the persimmon, the embryo instead of filling the 

 entire hull, lies embedded in a mass of nutritive substance. 

 This embryo can be seen beautifull}^ in the seed of a per- 

 simmon that has been split flatwise after a little soaking. 

 A seed then is a reproductive body of sufiicient size to be 

 easily seen, possessing a complex structure, and containing 

 an embryo which on sprouting becomes a .young seedling. 



Now how does a spore differ from a seed? In the first 

 place a spore is so small that it cannot usually be seen singly 

 Avith the unaided eye. If we press a puff-ball, a small cloud 

 of dust-like particles issues from it. Every particle of this 

 dust-like matter is a spore and the mass of them issuing 

 from the ball becomes visible because of the immense num- 

 bers. These spores are so small, that it would take about 

 5,000 of them laid side by side to make a line an inch long, 

 and a pufl^-ball an inch in diameter would contain many 

 millions of them. And yet each of these spores, consisting 

 of a mere skin containing a minute drop of a glairy fluid, 

 is capable, if placed under suitable conditions of heat and 

 moisture, of germinating into anew fungus like the one that 

 produced the spore in the first place. Another instance of 

 spores that are visible in the mass is seen in the ordinary 

 smut of corn or oats. The black smutted heads of oats are 

 made up when mature of a mass of black dust that easily 

 soils the fingers. Each particle of this black smut is a spore- 



