262 



MANUAL OF BOTANY 



The following forms have received distinctive names : — 

 1. The Sorosis is a collective fruit, formed of a number of 

 separate flowers firmly coherent with the floral axis upon which 

 they are situated into a fleshy or pulpy or sometimes almost 

 woody mass. An example of this may be seen in the Pineapple 

 (fig- 574), where each polygonal area represents a flower ; and 

 the whole is surmounted by a. crown of empty bracts. The 

 Bread-fruit and Jack-fruit are other examples of the sorosis. 

 The Mulberry (fig. 572) may be also cited as another well-known 

 fruit, which is constructed in the same manner. At first sight. 



FiGf. 572. 



Fig. 574. 



Fig. 573. 



Fig. 572. Sorosis or fruit of the Mulben-y (Morns nigra). Fig. 573. Fruit 



((?/((• /-/o) of the Raspberry {Rubiui Id(tius). Fig. 574. Pineapple fruit 



{.Surosi-H), surmouuted by a crown of empty bracts. 



the Mulberry appears to resemble the Raspberry (fig. 573), 

 Blackberry, and other fruits of the genus Ruhus, but in origin 

 and structure the latter are totally different. As already 

 noticed, the Raspberry and other fruits of the genus Ruhus con- 

 sist of a number of drupes crowded together upon a dry 

 thalamus, and are all the produce of a single flower. But in the 

 Mulberry, each rounded portion of which the fruit is made 

 up is derived from a flower, the calyx of which has become 

 succulent and united to the ovary ; the combination of a 

 number of flowers in this case therefore forms the fruit, while in 

 the Raspberry the fruit is produced by one flower only. 



