356 BOTANICAL GAZETTE [NOVEMBER 
was found to agree with the monocotyledonous type in general. 
The sequence in development was centrifugal and resulted ina 
well-defined endothecial layer, together with two or three inner 
wall layers in addition to the epidermis. At maturity only the 
epidermis and endothecial layer are present. 
The development of the archesporial nucleus shows some 
very important features. The coatracted condition called syn- 
apsis is without doubt a normal process accompanied by 
radical changes in the chromatin thread. The latter, which 
before synapsis was in the form of a network in which were 
imbedded large irregular chromatin masses, after synapsis is 
thicker, coil-like, and with the chromatin in smaller more equal 
masses. The spirem therefore begins at the close of the synap- 
sis stage. In both plants studied irregular dark masses were 
apparently expelled from the chromatin thread at the close of the 
synapsis, and in Potamogeton at least it was plainly evident that 
these had no connection whatever with the nucleolus. The ult 
mate fate of this chromatin-like matter was not determined. 
Whether this phenomenon was artificial or natural could not be 
determined from the material at hand. 
The growth and segmentation of the spirem in Convallaria 
almost identical with that in Lilium as described by oe. 
The longitudinal splitting of the ribbon is especially noticeable. 
In Potamogeton the process is different but could not be morse 
out satisfactorily owing to the minute size of the nuclei. * _ 
plant sixteen chromatin masses were counted just before division, 
but later there were only about seven, seeming to indicate a fusion 
of the widely separated primary segments to form the pn 
somes. The number of chromosomes after reduction was ©18 
een in Convallaria and seven in Potamogeton. This last nu™ 
ber is one of the smallest so far recorded for the phaser 
Spindle formation in all three plants agrees in every eee 
particular with the process described by Strasburget and pee 
for Lilium. The multipolar condition was evident in cace 
but was less distinct in Convallaria. 
The splitting of the chromosomes in the heteroty 
a is 
