152 



MOEPHOLOGY, OE COMPAEATIYE ANATOMY. 



Fig. 309. 



Sorosis. The Sorosis differs from the foregoing 

 by the substance of the constituent pericarps, 

 formed of the ovaries and floral envelopes of the 

 flowers, becoming pulpy and confluent with each 

 other (Morus, fig. 307), and sometimes with the 

 succulent axis of the inflorescence (Pine-apple, 

 fig. 308, Bread-fruit). 



Strobilus. The Strobilus, or Cone, is the cha- 

 racteristic fruit of the Gymnosperms, consisting 

 mostly of a conical or ovate mass of imbricated 

 scales, with seeds in their axils (or on their bor- 

 ders, Cycas), each scale being the development 

 of a single carpel, representing a female flower 

 (Finns, fig. 309). 



The Galbulus is a kind of cone with few scales, which 

 have their heads thickened and forming the periphery 

 of a somewhat globular mass, dry (Cupressus), or some- 

 times succulent (Juniperus, fig. 267). 



The Seed. 



Formation of the Seed. The consequence of the fecunda- 

 tion of the ovule is the development of an embryo in the embryo- 

 sac (p. 139) ; and during the maturation of the fruit the ovules are 

 perfected into seeds, the essential character of which is, that they 

 are independent reproductive bodies, containing an embryo or rudi- 

 mentary plant at the time when they are cast off by the parent 

 (fig. 311 B, e). 



Fig. 310. 



a - 



Fig. 310. Section of an Umbelliferous flower, showing the two seeds in situ, each containing 

 an embryo at the upper end, imbedded in albumen. 



Fig 311. Seed of Castor-oil plant (Ricinus) : A, external view : S, vertical section: a, hilum ; 

 b, micropyte, with an arillode around it ; c, raphe, leading to (d) the chalaza ; e, 

 embryo, with foliaceous cotyledons, and radicle pointing to the micropyle; f, peri- 

 sperm or albumen. 



