THE EMBRYO 



277 



and n', lying directly above the epiphysis initial e (Fig. 149F). Of 

 these, q gives rise to the cotyledonary region, m to the hypocotyl, 

 n or one of its derivatives to the hypophysis and a part of the sus- 

 pensor, and n' to the greater portion of the suspensor. Some of the 

 stages in development are shown in Fig. 149G-L. 



An epiphysis initial has also been reported in Fragaria and Viola 

 (Soueges, 19356, 1937c). The former is essentially similar to 

 Geum, but the latter shows some differences in that the derivatives 



Fig. 149. Development of embryo in Geum urbanum. (After Soueges, 1928b.) 



of the tier q, lying just above the epiphysis, produce not only the 

 cotyledonary region but also the lower portion of the hypocotyl, 

 while the tier m contributes to the upper portion of the hypocotyl 

 and the root. A suspensor is virtually absent, as the uppermost tier 

 ci is devoted to the formation of the root cap. 



Solanad Type. Soueges (19206, 1922) and Bhaduri (1936) have 

 studied a number of species of the Solanaceae, of which Nicotiana 

 may be described here as an example. The first division of the 



