214 GROWTH AND WORK OF PLANTS 



V. FRUITS OF GYMNOSPERMS. 



343. The fruits of the gymnosperms differ from nearly all of 

 the angiosperms in that the seed formed from the ripened ovule 

 is naked from the first, i.e., the ovary, or carpel, does not enclose 

 the seed. 



344. The cone-fruit is the most prominent fruit of the gym- 

 nosperms, as can be seen in the cones of various species of pine, 

 spruce, balsam, etc. 



345. Fleshy fruits of the gymnosperms. Some of the 

 fleshy fruits resemble the stone-fruits and berries of the angio- 

 sperms. The cedar "berries," for example, are fleshy and con- 

 tain several seeds. But the fleshy part of the fruit is formed, not 

 from pericarp, since there is no pericarp, but from the outer 

 portion of the ovule, while the inner portion of the ovule forms 

 the hard stone surrounding the endosperm and embryo. An 

 examination of the pistillate flower of the cedar (juniper) shows 

 usually three flask-shaped ovules on the end of a fertile shoot 

 subtended by as many bracts. The young ovules are free, but 

 as they grow they coalesce, and the outer walls become fleshy, 

 forming a. berry-like fruit with a three-rayed crevice at the apex 

 marking the number of ovules. The red fleshy fruit of the yew 

 (Taxus) 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. 



346. 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 



