certain Species of the Genus Christisonia . 135 
and not an endogenous one, as described for many other 
parasites ; it agrees in this respect with that of Rhinanthus . 
The young lateral roots and stems have both a similar 
origin from the parent-root ; they arise endogenously and from 
the central cylinder ; as they increase in age, this origin 
becomes more and more obscure, till it becomes a rather 
difficult task to determine whether it is a case of endogeny or 
exogeny. 
The degradation of structure in these plants we can trace 
through the stem and the foliar appendages up to the calyx, 
with which it ceases. The rest of the flower is chiefly 
distinguished by the mucilaginous covering of the corolla, the 
two spurred posterior anthers, and the motile stigma, the first 
and last characters, however, applying to one of the species 
only. 
This work has been carried out in the Botanical Laboratory 
of the Royal College of Science, South Kensington. I must 
express my warmest thanks to Professor J. B. Farmer, who 
collected the plants in their native habitat, for so kindly 
placing the material at my disposal for investigation, and also 
for the great assistance which he has continually afforded me 
throughout the progress of the work. I am also much 
indebted to him for the drawings of Figs. 1, 15, 16, and 17. 
EXPLANATION OF THE FIGURES IN PLATES 
V AND VI. 
Illustrating Mr. Worsdell’s paper on Christisonia. 
Pig. 1. Entire plant of C. subacaulis , Gardn., showing the disposition of the 
root, stems, and flowers. 
Fig. 2. Portions of the subterranean part of C. subacaulis , Gardn., showing the 
mode in which the roots anastomose together to form a tangled network, x i |. 
