538 OX SEEDLINGS 



yellowish externally ; cotyledons from an early stage becoming con- 

 cave, triangular or cucullate, conforming to the interior of the seed 

 with the endosperm inside or between them. As they progress to 

 maturity they develop along the base of the seed till they meet, with 

 the last remains of the endosperm between them. They now 

 become thicker, fleshier and more solid, wrinkled both externally 

 and internally and undulate at the margin whereby they firmly 

 interlock. 



Germination. The pericarp splits in the earth at the apex so 

 that the shoot and rootlet can emerge and develop. The two large 

 cotyledons rich in starch remain in the earth enclosed in the pericarp 

 and are gradually absorbed. The first leaf is entire. 



Fagus sylvatica, L. 



EAELY DEVELOPMENT OP FRUIT AND SEED. 



Pistil of three carpels and three-celled in the early stage with 

 very hairy loose dissepiments becoming easily detached from a 

 central, filiform, placental axis, traversing the whole length of the 

 ovary and bearing the ovules near the apex. 



Ovules two in each cell, making in ah 1 six, pendulous, anatropous ; 

 raphe ventral ; chalaza basal ; micropyle superior, elongated and 

 projecting into the neck of the ceh 1 below the base of the styles, and 

 considerably beyond the attachment of the ovule ; hilum ventral, a 

 little below the apex of the seed. 



After fertilisation and when the nut has attained its full size or 

 nearly so, one ovule only begins to enlarge rapidly while the others 

 become shrivelled and brown. This ovule is narrowly oblong, 

 pointed at the micropyle and obtuse at the apical and lower end, 

 with a distinctly prominent raphe and chalaza. Owing to the rapid 

 development of the ovary, the ovule is very short even after the nut 

 has nearly attained its full size. 



When the young seed has grown about half the length of the 

 ovary or more it becomes oblong and trigonous, in conformity with 

 the interior of the ovary. 



The coarsely hairy lines seen on each side of the placental 

 axis correspond to the original septa of the primarily three-celled 

 ovary. 



The embryo has its cotyledons already folded once in conformity 

 with the trigonous character of the fruit. A little later on the 

 cotyledons get too wide for the cavity of the fruit, and, con- 

 tinuing to increase, their edges become doubled back in two 

 of the angles of the seed, and the folds thus produced have the 



