1900 | LIFE HISTORY OF QUERCUS All 
upper regions they are separated by the complete fusion of the 
carpels. Each loculus contains two prominent placental folds 
(fig, 7, kk), and numerous hairs developing from the inner sur- 
face of the carpel. /ig.g is a longitudinal section through a 
carpel from material collected April 21. /%g. zo is a transverse 
section through the placental folds, which mark what may be 
regarded as the beginning of ovular development. 
Material collected May 5 shows the first indication of the 
integuments (fig. rz, ee). The nucellus now rapidly elongates 
by active cell growth and division, especially in the basal region. 
The integuments push forward at a still more rapid pace, and in 
a short time completely inclose the nucellus. In the meantime, 
growth being more active in the outer angle of the base of the 
ovule, it is forced to an erect position. ; 
ARCHESPORIUM. 
About the time the nucellus is fairly inclosed by the integu- 
ments there is a mass of from twenty to sixty or more cells in 
its upper half which clearly manifests an archesporial character. 
This character is manifested by a larger and clearer nucleus, a 
coarser linin net work, and larger granules, in contrast with the 
nuclei of the surrounding cells, while the cytoplasm takes a 
much deeper stain with Delafield’s heamatoxylin. In figs. 74-20 
the extent and position of this archesporial mass is indicated. 
Many ovules showing this stage were sectioned and figures could 
be indefinitely multiplied. 
In view of the usual record of events as they occur in the 
development of megaspore in angiosperms this archesporial 
Mass is marked by two striking peculiarities : (1) its unusual 
abundance, and (2) the cells are potential megaspores as Is 
proved by subsequent events. While multiple megaspores are 
known to occur in Rosa vida, and some of the Amentifere, 
Ranunculacee, Rubicez, and a few others, Casuarina is probably 
the only case hitherto known which strikingly resembles Quer- 
cus in this regard. 
This archesporial stage is of relatively long duration, appar- 
ently a period devoted to the accumulation of energy to be 
