THE DEVELOPMENT OF THE EMBRYO OF 
ENCEPHALARTOS 
W; 2: Saxton: ; 
(WITH PLATE II AND ONE FIGURE) 
Toward the close of 1906 Dr. H. H. W. PEarson offered to turn 
over to me some material collected' with a view to following the 
development of the proembryo and embryo of Encephalartos. We 
hoped to publish a joint paper, of which the present account, com- 
pleted two years ago, was to have been my contribution. As Dr. 
PEARSON now finds that the publication of his share will have to be 
delayed still further, he has suggested that I should publish the 
account separately. Iam glad to take this opportunity of thanking 
him for his help, and especially for the drawings to which his initials 
are appended. I also wish to thank Professor S—Ewarp for assisting 
me with the microphotograph from which jig. 18 is reproduced. 
All sections were cut with a Cambridge rocking microtome, 
except that from which figs. 76 and 17 were drawn, which was cut 
by hand. All figures were drawn with the aid of a Zeiss camera 
lucida, microscope, and lenses, except jig. 18, which is from a micro- 
photograph. Figs. 1, 2, 6-8, 12-15 were drawn by Dr. PEARSON, 
the others by myself. 
The material at my disposal afforded a fairly complete series 
of the development of the embryo, but the stages to illustrate the 
proembryo and early post-fertilization stages are almost entirely 
wanting and will not be referred to. The first account of embryo 
development in cycads seems to have been that by WaRminc? for 
Ceratozamia, but only a very few stages are described and figured. 
Proembryo development has been described in Cycas by TREuB? and 
« With the aid of a grant from the British Association for the Advancement of 
Science. 
2 WarminG, E., Undersogelser of Betragtninger over Cycadeerne. 1877. 
3 TrevuB, M., Recherches sur les Cycadées. 3. Embryogénie du Cycas circinalis. 
Ann. Jard. Bot. Buit. 4:1-11. pls. I-3. 1884. 
13] [Botanical Gazette, vol. 49 
