Davey.— Seedling Anatomy of certain Anientiferae . 597 
Of the smaller epigeal seedlings many are tetrarch, but very often the 
four poles are well differentiated only at low levels in the hypocotyl near 
the collet. The most extreme instance of this is furnished by Myrica Gale 
(see p. 583). It occurs also in Carpinns and Almis. The intercotyledonary 
protoxylem poles persist upwards to a varying degree, but die out near the 
cotyledonary node ; while the metaxylem diverges and passes out as part of 
xili. Castanea sativa. xiv. Fagus sylvatica „ 
the cotyledonary traces. In some cases the whole of the triad strand is 
divided between the cotyledons. 
It is probable that here also the intercotyiedonary centres are differen- 
tiated in relation to the plumular traces, which are frequently double 
strands. Since the plumular development is so much delayed, differentia- 
tion is not complete at the upper end of the seedling, so that the protoxylem 
