OF CoOOPERIA DRUMMONDII 399 
from its stand and placed upon a ground glass plate below which 
in a convenient compartment was an electric light bulb. A glass 
plate, bearing the imbedding ells, was placed on the arms of the 
stage. The light from the electric bulb readily made visible the 
gross structure of the embryo, so that the orientation of the 
object could be positively determined. Care was taken not to 
overheat the lenses of the binocular by leaving the electric bulb 
lighted for too long a period. The imbedding was done therefore 
quite rapidly. Serial sections 10-12 in thickness were cut. 
Delafield’s hematoxylin; Haidenhain’s iron-alum haematoxylin 
with fuchsin, erythrosin or Orange G; thionin with erythrosin; 
and Flemming’s triple stain were used. The last gave the best 
results. 
Very early in the development of the ovule, the primitive 
archesporial cell, which is hypodermal in origin, may be distin- 
guished from the surrounding somatic tissue by its size, its granular 
content and its prominent nucleus (Fic. 1). Two hypodermal 
cells in one ovule were noted in five examples out of one hundred 
and forty-six ovules examined (Fic. 2). It was not possible to 
follow the subsequent development. Guignard (4) reported this 
condition in Ornithogalum pyrenaicum, and similar instances have 
been found in an increasing number of the Liliaceae. See Coulter 
and Chamberlain (1), Lechmere (6), and McAllister (8, 9). At 
this time the integuments of the ovule are not~visible. The 
archesporial cell develops at the expense of the surrounding 
nucellus into a large oblong cell, which stands with its longer 
axis parallel to that of the ovule (Fic. 3). No tapetal cells were 
observed. The absence of a parietal tissue occurs among some of 
the close relatives of the Amaryllidaceae, as in Allium, H. emerocallis, 
Lilium, and Erythronium of the Liliaceae; and in Sisyrinchium 
iridifolium and Iris stylosa of the Iridaceae (Coulter and Chamber- 
ain, 1). 
Megaspore formation takes place in the way usual for the 
Liliaceae. The archesporial cell becomes directly the one-celled 
stage of the embryo sac (Fic. 3). It was not possible to follow 
out the behavior of the chromosomes in any of the divisions of 
the embryo sac nuclei. Since the mode of development of the 
embryo sac of Cooperia Drummondit is similar to that of Ery- 
