THE EMBRYO 



205 



eially characterized by its extensive, worm-like, and large-celled 

 suspensors, whose cells often break apart. The suspensor may 

 consist of twenty pairs of elongated cells, forming a tortuous 

 filament extending the entire length of the embryo-sac, with a 

 very small embryo at the tip, as in L. subcarnosus ; or it may be 

 a filament of short, very broad cells, suggesting a leech in ap- 

 pearance, as in L. pilosus; or it may be a loose, large-celled 

 tissue lying along the cavity of the embryo-sac, actively dividing 

 and more or less surrounding the late-forming embryo with its 

 rounded cells, that finally break apart and become disorganized, 

 as in L. polyphyllus, L. mutabilis, L. truncatus, etc. 



The degree of development of the embryo is extremely vari- 

 able. In some cases a plumule with several leaves is formed, and 



Fig. 98.— Embryos of Leguminosae. A, Lupinus subcarnosus, with long sinuous sus- 

 pensor and small four-celled embryo (e) ; x 270. B, L. luteus, with many suspensor- 

 cells binucleate; x 160. C, L. pilosus, with some basal suspensor-eells isolated; 

 x 80.— After Guignard." 



even lateral roots appear, as in Gramineae, Impatiens, Cucur- 

 bita, Trapa, etc. ; while in many parasites and saprophytes the 

 embryo is represented only by an undifferentiated mass of cells. 



