63 



I 



0k 



The principal difference from the usual manner of germinat- 

 ing consists in the presence of a cotyledonar sheath, formed 

 , by the petioles of the cotyledons, which are connate, 

 forming a long tube, at the base of which is a small 



1^. slit for the penetration of the plumule (Plate VI, Fig. i8 SI). 



The cotyledons are long-petloled, with the blade ovate, 

 slightly acute at the apex, and the two blades show also a 

 tendency to grow together at their very base, leaving only a 



I minute opening in the middle, representing the superior end 



of the tube. In one case (Fig. 17) there were developed 

 three cotyledons, of which the blades were all equal in size 

 and each of which showed the same nervation, so that it was 

 certain that no division had taken place. 



As to the primary root, this is relatively very large in the 

 youngest state of the plant and shows early several lateral 

 branches, which are densely covered with long root-hairs. 

 Fig. 17 shows the first leaf coming out through the slit at the 

 base of the tube. The cotyledons are persistent for a long 

 time and do not fade away until four or* even five leaves have 

 been developed. The primary root is persistent as long as 

 the plant lives, and increases gradually in thickness and ram- 

 ification. 



SARRACENIACE^. 



I 



Sarracenia purpiirea. 



Two gerhiinating plantlcts of this species were figured 

 many years ago by Schnizlein,* and the figures show very 

 exactly the part above ground : that is, the hypocotyl, the 

 cotyledons and the first leaves. Further, in regard to the 

 germination, Gray has described the cotyledons as being 

 ** short," which is, however, not correct according to the fol- 

 lowing observations, which have been made on numerous 

 seedlings cultivated in the U. S. Botanical Garden. 



A very early stage of the germination has been figured 

 on Plate VII, Fig. 23, where we see the rather long, linear 

 cotyledons, carrying tlic testa of the seed at their summit, the 





* A. Schnizlein : Iconographia fam. nat. regni veget, 1S43-46, Plate 1S5, 

 Figs, 19 and 20, Asa Gray ; Genera Flor. Boreali — Orientalis illustrata, 

 vol. I, 1848, p. 108. 



