49, 50.] THE OVULES. 59 



position, the ovule is erect when it grows upward 

 from the base of the cell, as in Compositse ; ascending, 

 when it turns upward from the side of the cell ; hori- 

 zontal, when neither turning upward nor downward; 

 pendulous, when turned downward ; and suspended, 

 when growing directly downward from the top of the 

 cell, as in Birch (158-161). 



140. The ovule at the time of flowering is soft and 

 pulpy, consisting of a nucellus within two coats, sup- 

 ported on a stalk. The stalk is called funiculus ; the 

 point of its juncture with the base of the nucellus is 

 the chalaza. The nucellus was first formed ; then the 

 tegmen, or inner coat, grew up from the chalaza and 

 covered it; and lastly the outer coat, the testa, in- 

 vested the whole. Both coats remain open at the top 

 by a small orifice, the foramen. 



141. In most cases the ovule, in the course of its 

 growth, changes position curving over in various de- 

 grees upon its lengthening funiculus or upon itself. 

 When no such curvature exists, and it stands straight, 

 as in the Buckwheat order, it is orthdtropous. It is 

 anatropous when completely inverted. In this state a 

 portion of the funiculus adheres to the testa, forming 

 a ridge called raphe, reaching from the chalaza to the 

 hilum. It is campylotropous when curved upon itself. 

 In this state the foramen is brought near to the cha- 

 laza, and both are next the placenta, as in the Pinks 

 and Cruciferse ; and amphitropous when half inverted, 

 so that its axis becomes parallel with the placenta, as 

 in Mallow. Here the raphe exists, but is short. In 

 campylotropous ovules there is no raphe. 



142. The ovule contains no young plant (embryo) 

 yet ; but a cavity, the embryo sac, is already provided 



