150 
CHARLES J. CHAMBERLAIN 
In trying to provide progeny for the Cycadophytes, some have cast a 
hopeful eye upon the Gne tales, because the staminate flower of Welwitschia 
has a sterile ovule and thus presents a bisporangiate condition in which a 
vivid imagination might see some resemblance to the bisporangiate strobili 
of the Bennettitales. But my imagination is too weak to see more than a 
superficial resemblance, even in this feature; while a comparison of the 
stems of the two phyla, the comparison of pinnate leaves with simple 
leaves, and of simple strobili with compound strobili, seems impossible. 
Could the Cycadophytes have given rise to the Angiosperms? 
For the living cycads, we should answer with a positive no. This con- 
clusion cannot be escaped, if we compare the haustorial pollen tube and its 
contents with the sperm-carrying pollen tube of the Angiosperms. The 
large, ciliated, highly differentiated sperms of the cycads are headed for 
extinction rather than for evolution into the comparatively simple structures 
of the Angiosperms. The extensive free nuclear period in the development 
of the cycad embryo does not compare well with the total lack of such a 
period in the Angiosperms. However, reductions in the free nuclear period 
are not entirely impossible. 
It is true that the general habit of the cycad, with its unbranched stem 
and crown of pinnate leaves which form an armor of leaf bases, is so strongly 
suggestive of palms that the layman calls Encephalartos the "Bread palm," 
Dioon the "Dolores palm," Cycas the "Sago palm," etc. But the resem- 
blance is superficial. A section of the palm stem shows an advanced mono- 
cotyl condition, and the flower is truly monocotyl. It may seem like begging 
the question to say that the Monocotyls have come from the Dicotyls, 
but we believe this has been proved as definitely as anything is likely to be 
proved in relationships. 
The resemblance between the Bennettitales and the Angiosperms is 
about the same ; but here an attempt has been made to reconcile the floral 
structures. The resemblance pointed out was between the Bennettitales 
flower and a sympetalous flower. Our objection here would be along the 
same line : the sympetalous condition is a modification of the polypetalous, 
and the Sympetalae, like the Monocots, have come from the Archi- 
chlamydeae. 
In the Cycadofilicales we are nearer the source of things, but the dis- 
crepancies keep becoming greater and greater and indicate that we are on 
the wrong trail. Like the hasty student, trying to pigeon-hole Eryngium 
yuccaefolium among the Monocots, we need to go back and make a fresh 
start. 
We have tried to show that the Cycadophytes have come from the 
ferns, by way of the Cycadofilicales directly or as an early branch from the 
Bennettitales; and we have also tried to show that they have not given 
rise to any other seed plants. 
This might seem like a logical place to stop, for we have tried to answer 
