342 CHURCH: THE BULB IN COOPERIA DRUMMONDII 
exogenous lateral outgrowth upon the growing point of a stem as 
do the later foliar structures, therefore, said cotyledon, occurring 
in the mature seed plant at the base of the primary stem, is more 
closely related to the nursing foot of the bryophytes. The succu- 
lent cotyledon of the young plant of Cooperia Drummond in 
anatomical structure and size is well adapted to serve as an 
absorption organ. 
SPROUTING OF THE SEED 
The ripe seed of Cooperia Drummondii was described by 
Herbert (13) as having a brittle, shiny black seed coat and in- 
clined to be wedge-like in shape. The seed coats are slightly torn 
at the time of sprouting as the root pushes through the very 
small micropyle, but they are never split apart into halves. On 
February 20, 1914, the seeds from a ripe pod were immediately 
placed upon wet filter paper on the sides of a moist chamber at 
ordinary room temperature. Three days later—February 23— 
the seeds had sprouted and the roots on the seedlings averaged 4 
mm. in length; on February 25 the root length was Io-12 mm., 
while at thirty days of age the root length was 65 mm. If, how- 
ever, the seeds were well dried and allowed to remain dry for 
several months at the temperature of the laboratory they did not 
sprout so readily. 
The future root and shoot of the embryo are pushed out of 
the seed coats by a lengthening of the cotyledon, as well as by 
the growth of the root- and shoot-regions. Solms-Laubach (30) 
notes a similar condition in Heterachtia. 
The portion of the cotyledon between the micropyle region 
of the seed coats and the surface of the soil becomes a brilliant 
green, indicating the formation and presence of chlorophyll here. 
The cotyledon therefore functions in part as a leaf, aiding the 
leaf blades in the photosynthetic processes of the plant’s activities. 
The leaf grows upward to the light above the ground, while the 
cotyledonary sheath serves as a protecting sheath in the same © 
fashion as the encircling leaf base of any subsequent leaf serves 
as a sheath for the next younger leaf (Fic. 4). The region bounded 
by the root, the cotyledon and the plumule was designated by 
Richard (29) in 1808 as the ‘“‘tigelle,” corresponding as he said 
to the Latin term “‘cauliculus.”’ The ‘‘tigelle’’ he defines as 
