584 



BOTANY 



3. When a dry fruit, consisting of several carpels, separates at 

 maturity into its partial fruits without the latter opening, it is 

 termed a SCHIZOCARP (e.g. Umbelliferae, Malm, Galium, Fig. 572). 



4. A BERRY (Fig. 573) is a fruit in which all the layers of the 

 pericarp become succulent, as in Vaccinium, Fitis, etc. 



5. In the DRUPE the pericarp is differentiated into a succulent 

 exocarp and a hard endocarp. Prunus Cerasus (Fig. 697) and Juglans 

 regia (Fig. 602) are familiar examples. 



When, on the other hand, the group of fruits borne on an 

 inflofescence has the appearance of a single fruit, the structure may be 

 termed a SPURIOUS FRUIT. The Fig (Ficus) is the best-known example 

 of this, but similar spurious fruits are especially frequent in the 

 v^ Urticaceae and Moraceae. The com- 



& i parison of a Blackberry which is 



the product of a single flower with 

 the spurious fruit of the Mulberry 



Fia. 573. Fruit of Physalis alkekengi, 

 consisting of the persistent calyx 

 s, surrounding the berry fr, derived 

 from the ovary. (After DUCHARTRE.) 



FIG. 574.^, Collective fruit of Rubus fruti- 

 cosus, consisting of a number of drupes. 

 B, Inflorescence of Mulberry (Morus nigra) 

 bearing a number of small drupes. (After 

 DUCHARTRE.) 



will show how closely the two structures may resemble one another 

 (Fig. 574). 



Distribution of Seeds ( 12 ) 



The most important means by which Spermatophytes compete with 

 others living under the same conditions is to produce as many seeds 

 as possible. With the number of descendants the probability that some 

 at least will succeed is increased. The number of seeds by itself 

 would, however, be of little avail if all the seeds remained in the place 

 of their origin. Thus good arrangements for the distribution of the 

 seeds are of the greatest importance, and the form and construction of 

 fruits and seeds exhibit the great influence of this factor. 



The same agents are available in the distribution of seeds as in 

 the conveyance of pollen -currents of air and water, animals, and in 

 addition human traffic. A distinction must be made, however, between 

 the conveyance of pollen and of seeds, in that while a pollen grain is 



