THE FRUIT: "FRUIT" OF FERNS, MOSSES, ETC. 



resembles a drupe which is open at the apex. The stony seed is 

 formed from the single ovule on the fertile shoot, while the red cup- 

 shaped fleshy part is formed from the outer integument of the 

 ovule. The so-called " aril " of the young ovule is a rudimentary 

 outer integument. 



333. The fruit of the maidenhair tree (Ginkgo) is about the 

 size of a plum and resembles very closely a stone-fruit. But it is 

 merely a ripened ovule, the outer layer becoming fleshy while the 

 inner layer becomes stony and forms the pit which encloses the 

 embryo and endosperm. The so-called " aril," or " collar," at 

 the base of the fruit is the rudimentary carpel, which sometimes is 

 more or less completely expanded into a true leaf. The fruit of 

 Cycas is similar to that of Ginkgo, but there is no collar at the base. 

 In Zamia the fruit is more like a cone, the seeds being formed, 

 however, on the under sides of the scales. 



VII. THE "FRUIT" OF FERNS, MOSSES, ETC. 



334. The term " fruit " is often applied in a general or popular 

 sense to the groups of spore-producing bodies of ferns (fruit-dots, 

 or sori), to the spore capsules of mosses and liverworts, and also to 

 the fruit-bodies, or spore-bearing parts, of the fungi and algae. 



