*92o] • HAJNING—GNETUM 



439 



ma) 





There are no nuclei distributed along the suspensors. 



The condition of the tubes just described is that found in the 

 ripe fruit on the trees, and in many of the seeds on the ground. At 

 the next stage the suspensors swell to about five times their original 

 size, and sometimes curve about as in fig. 5. The end cell widens, 

 and moving out from the surrounding protoplasm crowds into a 

 protrusion of the gelatinous wall of the tube (fig. 10). Division 

 takes place first into two cells (fig. 11); then each of these divides 

 again, forming the four cells shown in fig. 12. In this preparation 

 one of the walls is not visible. The cells continue to divide in an 

 irregular manner, forming an ovoid group (fig. 13). Division 

 continues with elongation of the basal cells. The result is the 

 formation of a long ribbon of tissue (fig. 14) which, like the primary 

 suspensors, is folded in the cavity of the endosperm. This sec- 

 ondary suspensor, usually measuring about 13 mm., is formed of 

 rather long thin-walled cells with large nuclei. This multicellular 

 ribbon is very different from the secondary embryonal tubes of 

 Abietineae, and, on the other hand, is not found at all in G. Cnemon, 

 according to Bower and Coulter. At the basal end of this 

 secondary suspensor a chain of smaller cells with denser nuclei is 

 differentiated, which may function in the proliferation of embryos. 

 At the apex of the secondary suspensor the cells are actively meri- 

 stematic (fig. 15). When the suspensor has lengthened sufficiently, 

 it is the rapid multiplication of this group of cells which forms the 

 massive embryonic body. 



This embryonic body differentiates in a manner similar to that 

 described for G. Cnemon by Bower (i). Fig. 22 shows the first 

 stage as it appears externally. At the apex a conical projection 

 is visible, surrounded by a thick ridge, from which the cotyledons 

 develop. Fig. 23 shows the "foot" or " feeder" projecting from 

 the side of the hypocotyledonary stem. In fig. 24 both hypocotyl 

 and "foot" have elongated, the latter having exceeded the former. 

 Growth continues as shown in fig. 25, and the radicle reaches the 

 micropyle. After forcing its way out of the endosperm, the radicle 

 turns downward. Then the hypocotyledonary stem grows rapidly 

 and makes its way out of the endosperm also. Following this, the 



