THE FRUIT AND SEED-DISPERSAL 



329 



Buttercups, or in the Hounds-tongue (Cynoglossum) (C) they are on 

 tho superior achene : in the Water Avens (Genm rivale) (D) a single 

 hook is formed half way up the style of each carpel. Such instances 

 taken from different families, and involving quite 

 different parts, show that these effective develop- 

 ments have originated repeatedly, and indepen- 

 dently of one another. 



A second and more prevalent means of dispersal 

 is internally, as ingested food. It is secured by 

 development of succulent tissues in close relation 

 to the seeds. Here it is found that most diverse 

 parts are involved, even in nearly related plants. 

 Pulpy fruits occur in almost every family ; even 

 among the Grasses, which have characteristic dry 

 grains, certain Bamboos bear a succulent fruit. 

 The pulpy tissue often involves the whole carpel- 

 lary wall, and the seeds are embedded in it : this 

 is the case in the berries of the Grape, or Currant, 

 the one being a superior the other an inferior 

 ovary (Fig. 252). Or it may be only the outer 

 part of the wall that is pulpy, while the inner is 

 stony, as in the drupe of Cherries or Plums (Fig. 253). Sometimes 

 parts other than the pistil itself may be involved, for instance the 

 receptacle may be convex, and succulent, and bear the dry achenes 

 (which are the true fruits in the restricted sense) upon its surface, as in 



Fig. 252. 



Berries of the Currant. 

 (After Figuier.) 



Fig. 253. 



Drupe of Cherry. 

 Figuier.) 



(After 



Fig. 254. 



Succulent receptacle of Strawberry. 

 (After Figuier.) 



the Strawberry (Fig. 254). Or it may be concave, and the achenes 

 be borne within its hollow cavity, as in the " hip " of the Rose. In 

 the Fig it is the massive axis of the condensed inflorescence that 



