148 
CHARLES J. CHAMBERLAIN 
The megasporophyll of Cycas is of the greatest importance in tracing 
relationships, for it is essentially identical with the megasporophyll of the 
Paleozoic genus Pecopteris; while in the living cycads, a series of genera like 
Cycas, Dioon, Macrozamia, and Encephalartos shows the gradual reduction 
of the individual sporophyll and, at the same time, shows how a loose crown 
of sporophylls has been compacted into a cone (Plate VI). 
This megasporophyll of Cycas is so different from any yet described in 
the Bennettitales that we think it is safe to claim that the Cycadales have 
not ccme from any forms like Cycadeoidea, or from any others with such 
reduced seed-bearing structures. While we shou'd recognize the phe- 
nomenon known as atavism, or reversion, we believe it could appear only 
after a rather limited time. We can easily believe that a Pecopteris-like 
megasporophyll has persisted from the Paleozoic up to the present time; 
but we could not believe that the megasporophyll of Cycadeoidea, if re- 
duced from a Pecopteris type, could — after millions of years — revert to the 
Pecopteris type, and so give rise to a megasporophyll like that of Cycas. 
We might believe in spontaneous generation and in the special creation of 
species, but not in that. 
Consequently, if the Cycadales are a branch from the Bennettitales, 
the point of union is so far back that it becomes a question of arbitrary 
definition rather than a question of fact whether there has been a main 
stock with an early branch, or whether there have been simply two lines 
coming independently from the Cycadofilicales. 
This seems to me to answer the question, "What was the origin of the 
living Cycads?" as far as it can be answered in the present state of our 
knowledge. If Professor Wieland would give us three big books on the 
Cycadales of the Triassic, Jurassic, and Cretaceous, like his three big books 
on the Bennettitales, we could state facts instead of spinning theories. 
In tracing the plane body, with its stem, leaves, and spore-producing 
structures, from the Paleozoic up to the living cycads, the record is fairly 
complete, and there is not a very serious danger of mistakes ; but in tracing 
the origin of the seed the Cycadophyte line has afforded little evidence, 
for the seeds — as far as they have been described — are almost as highly 
developed in the Paleozoic as they are today. In this line, they must have 
come from heterosporous ferns. But, until some one finds and sections a 
convincing series in heterosporous ferns, or in some more primitive members 
of the Cycadofilicales than any yet discovered, we must base our theories 
of the origin of the seed upon the behavior of living heterosporous forms 
which have not quite reached the seed stage. 
What is the answer to the second question, "Have the Cycads left any 
progeny? " 
Something has left some progeny; for an abundant progeny, both Angio- 
sperm and Gymnosperm, is very visible and very much alive. What 
groups could have been responsible for this progeny? 
