110 CARPOLOGY: FUNCTIONS AND STRUCTURE OF THE FRUIT 



winter use. The edible portion is in some cases, as in that of the banana, 

 highly nutritious, while in others it is apparently eaten merely for its 

 palatability or for its thirst-quenching properties. 



Sixcial Protection to Seeds of Edible Fruits. — Some special form of 

 protection is commonly required for the seeds of edible fruits. That 

 of the peach is enclosed in a hard stone, so that it shall not be abraded 

 as the pulp is pecked or bitten away. Those of the cherry and straw- 

 berry are enclosed in similar hard coats, which resist the digestive process 

 as well. The more or less laxative or purgative properties of many 

 fruits doubtless contribute to such protection by the more prompt 

 dejection of the seeds which is brought about by their action. 



Jm 



Fig. 301. Lappa fruit with prickly involucre. 302. Fruit of Geum with jointed style. 303. Fruit 

 of Gaultheria, with fleshy calyx. 304. Of strawberry, with fleshy torus. 305. Of blackberry, with 

 fleshy torus and ovaries. 306. Of cashew, with fleshy pedicel. 307. Of tamarind, with fleshy middle 

 layer of pod. 308. Of apple, with fleshy calyx and disk. 309. Of papaw, with fleshy inner layer of 

 ovary. 310. Of belladonna, with fleshy ovary. 311. Of fig, with fleshy hollowed end of branch. 

 312. Of watermelon, with fleshy placentae. 



Origin of Edible Portion. — The origin of the edible portion is vai'ious. 

 In the strawberry (Fig. 304) it is the complete torus, and this only. In 

 the blackberry (Fig. 305) such a torus is combined with a partially 

 fleshy ovarian wall upon each of the ripened pistils. In the rose (Fig. 

 59) it is a similar torus, but hollowed, probably with other elements 

 combined. In the apple (Fig. 308) it is a fleshy-thickened disk, together 

 with the adnate calyx lined by it. In the checkerberry (Fig. 303) it is 

 the calyx only which becomes fleshy. In the gooseberry it is the calyx 

 and the entire ovary, but without any disk, while in many other berry- 

 like fruits it is the ovary alone. In the plum and cherry not all of the 



