The Structure of the Gyaise Integuments and 
the Development: of the Testa in 
Cleome and Isomeris. 
BY « 
MATTHEW YOUNG ORR, 
Assistant in Laboratory, Royal Botanic Garden, Edinburgh. 
With Plate CLXVII and four figures in the text. 
In the course of an investigation on the anatomy of the ovules 
and seeds of the Capparidaceae, certain interesting features * 
were disclosed in the Cleomoideae section of the family, which 
may or may not be characteristic of the family as a whole, 
but which certainly appear to be sufficiently distinctive to merit 
a separate detailed description. 
The species upon which this research was carried out were 
Cleome spinosa, Jacq., and Isomeris arborea, Nutt., and the 
material was obtained from living plants grown in the Royal 
Botanic Garden. The ovaries and fruits were fixed in chrom- 
acetic acid, and the microtomed sections were variously 
stained, the best results being secured with a combination of 
gentian-violet and eosin. 
The general features of the campylotropous ovules and seeds 
of these species are so well known that they will only be referred 
to in passing, the main purpose of this paper being to direct 
attention to two of the outstanding anatomical features, namely, 
the genesis of the fibrous testa, and the occurrence of stomata in 
the outer integument of the ovule. In these points Cleome and 
Isomeris have so much in common that the detailed description 
will be confined to the former, and merely a brief note of the 
points of difference will be made in the case of [someris. Apart 
from the anatomical peculiarities, it will be observed that the 
physiological aspect of the structures described is also suggestive. 
* The features described in this paper were not noted by Brandza in his 
dissertation, “‘ Développement des Téguments de la Graine” (Rev. gén. bot., iii, 
1891, p.' 73), or by Guignard in his researches on the “ Tégument séminal ” 
(Journ. de bot., vii, 1893, p. 57): Both these authors included the Capeeriaarcee 
in their works 
[Notes, R.B.G., Edin, No. LX, January 1921.] 
