260 ORR—SEED IN CAPPARIDACEAE AND RESEDACEAE. 
The occurrence of a third seed-coat in the seeds of the 
Resedaceae is mentioned by Baillon * in his description of the 
seed of Reseda odorata, but no anatomical details are given. 
Mueller + in his monograph of the family, also briefly refers to 
this tissue, and it is indicated by Harz ¢ in his figure of a cross 
section of the seed of Reseda luteola, but neither of these investi- 
gators makes any reference to the peculiar configuration of its 
periclinal cell walls, which is only visible in surface view. 
For a description of the features of this differentiated tissue 
in the seeds of the Resedaceae, that of Reseda glauca, Linn., 
may be taken as typical of the family. 
In dissections of the seed, it appears as a yellow pellicle, 
which adheres to the inner wall of the tegmen, and completely 
encloses the embryo. The cells of the outermost layer of this 
tissue are devoid of living contents, and are approximately 
.05 mm. long by .025 mm. broad. 
In surface view, under the microscope, it is seen that their 
periclinal walls are clearly marked with numerous fine annular 
bands of thickening, producing the effect of finger-prints, and 
having the same appearance, but on a larger scale, as that pre- 
sented by the corresponding tissue in the seeds of Polanisia 
and other genera belonging to the Cleomeae tribe of the Cap- 
paridaceae. 
It is thus apparent that the seeds of those species of the 
Resedaceae and Capparidaceae which have been examined 
exhibit a striking similarity in their construction, for both 
families possess this unusual feature of a specialised tissue, 
forming a third seed-coat, the configuration of which, as seen 
in the seeds of the Resedaceae, is identical with that found in 
the Cleomeae among the Capparidaceae. 
This anatomical feature has every appearance of an additional 
link between the two families, and, though it might be regarded 
as a minor character, its presence is nevertheless suggestive of 
the close affinity of the Resedaceae to the tribe Cleomeae of 
the Capparidaceae. 
* M. Baillon, Natural History of Plants, vol. iii Rte: p. 296, footnote. 
Tt c Mueller, Monographie des Résédacées (1857), p 
{ C. D. Harz, Landwirthschaftliche Samenkunde (885), vol. li, p. 987. 
EXPLANATION OF PLATE CLXVIII. 
Illustrating Mr. M. Y. Orr’s paper on the ae. of the Seed in the 
apparidaceae and Resedac 
Fic. 1 FS aa ace of a portion of the specialised layer surrounding the embryo 
n the seeds of Polanisia viscosa, DC. xX about 430 
Figs, 2 and mae tographs of a portion of the corresponding thabia in the seeds 
of Reseda spt Linn. x about 430. 
