1904 | SARGANT: EVOLUTION OF MONOCOTYLEDONS 345 
for many years later is a squat axis surrounded by successive 
leaf bases. The primary root is vigorous and persists for some 
time, but in the end it is always replaced by a number of much 
stouter cauline roots: In fact, if a young palm, such as is com- 
monly sold for table decoration, be halved longitudinally, it is 
seen to be formed on the model of a bulbous plant. Its struc- 
ture in youth may certainly be interpreted as a reminiscence of 
geophilous ancestry. 
CONCLUSION. 
In this account of a new view on the evolution of monocotyle- 
dons, I have tried to show that it is the most consistent —as in 
practice I have found it the most suggestive— among existing 
hypotheses. 
An immense amount of work remains to be done on the 
Structure, both external and internal, of seedlings before this or 
any other suggestion can be generally accepted as representing, 
€ven in outline, the real sequence of events. We need observers 
to carry on the work so well begun by Irmisch; monographs 
like those of Mr. Holm on Podophyllum and Erigenia; the 
detailed work of anatomists like Professor Jeffrey and M. Quéva. 
Even if no direct evidence should be contributed from the 
Seological record, there is little doubt that the key to the descent 
of monocotyledons will be found in their morphology. 
QuaRRy HILL, REIGATE, ENGLAND. 
