396 PROF. F. W. OLIVER ON THE STRUCTURE 
In conclusion, I would express my obligations to Dr. Smith Woodward, F.R.S., to 
whom I am indebted for access to the Williamson and other collections in the 
Geological Department of the Natural History Museum, and for facilities in preparing 
sections of some of the seeds in his custody; to Mrs. A. G. Tansley, who has rendered 
great assistance in preparing sections of recent plants for purposes of comparison; and 
to Dr. D. H. Scott, F.R.S., who has given me much encouragement in the course of 
this investigation. My thanks are also due to Mr. A. K. Coomáraswámy and to 
Mr. W. Tams for the photographs which accompany this paper. 
[The opportunity afforded by the passage of this paper through the press has been 
utilised to revise certain portions in correspondence with the facts that have accrued 
since it was written.— F. W. O., February 1904. | 
EXPLANATION OF THE PLATES. 
Figures 1-16, Stephanospermum akenioides ; 17-20, Stephanospermum caryoides : all taken direct from 
the sections. Almost all should be examined with the aid of a lens. Figures 1-16 are from photographs 
by Mr. W. Tams, of Cambridge; 17-20 by Mr. A. K. Coomáraswámy, B.Sc., F.L.S. Figures 29, 38, 
41, and 43 are from drawings by Mr. G. T. Gwilliam. 
PLATE 41. 
Stephanospermum akenioides, Brongniart. 
Figs. 1, a En, Median longitudinal section of apex and base. A narrow zone from the middle part of 
the seed alone is unrepresented in the two figures. The most noteworthy feature here 
shown is the relation of the collar to micropyle and nucellar apex. Shown on a large scale 
in Pl. 43. fig. 29. c., crown; co., collar; end.t., remains of endotesta; n.e., epidermis 
of nucellus; pa., basal papilla ; p.c., pollen-chamber, much macerated ; ¢.d., tracheal disc 
at the chalaza; v.5., the entering vascular bundle. x15. S 64*. (See pp. 363, 365.) 
Fig. 2. Median longitudinal section of micropyle and pollen-chamber. In the latter is a cluster of 
pollen-grains excellently preserved. Figs. 14 and 16 show the pollen under higher magni- 
fication, as also do figs. 30, 31, and 35. co., collar, cut a little tangentially; k., remains of 
hairs which lined the perimicropylar trough; m.w., wall of macrospore ; s. is level with 
the remains of septum between the pollen-chamber and the supra-archegonial gap (s.@.g.)5 
sh., shoulder (i. e., tissue of nucellus forming side of pollen-chamber). A more highly 
magnified view of a portion of the shoulder is given in fig. 11. x15. S74. (See 
p. 369.) 
Fig. 3. Median longitudinal section through pollen-chamber with pollen. Most of the grains are 
congregated near the apex of the chamber, a few (p.) with the small abortive grains 
adjacent to it and the abortive grain (p.’) have been drawn down, previous to mineralisaticn, 
/.* The reference letter and number refer to the slides upon which the photographs or drawings are based. 
Where not specially indicated, the slides are in the University College collection, 
