C. A. BARBER. 7 
young and old stages of the plants. For the illustration of these 
points the reader is referred to the figures on Plates I and IT. 
5. The haustoria of Olax scandens differ but little in 
appearance from those of Santalum album. More or less conical, 
whitish as a rule, but frequently discoloured grey or brown by 
the surrounding earth or, in older specimens, by the corky 
layers formed and, in the latter case, lacking the bright red-brown 
colour of the sandal root-system. The older haustoria are per- 
haps more irregular than those of sandal and appear, on the 
whole, more frequently to be compressed and distorted or flatten- 
ed, scale-like and circular. In size there is little to separate the 
two, the ordinary haustoria in Olax beng 1—5 mm. high, 5—10 
mm. long and 4—8 mm. broad (Plate II, figs. 5—8 of which 6 and 
7 are of natural size). 
Occurring as it does in thickets, Olax scandens has abund- 
ant roots at hand to which to attach itself, and examination 
shows that it avails itself very readily of the opportunity. It 
was also noticed at the very commencement with what frequency 
self-attachment occurred in nature. Indeed, the very first speci- 
men which drew attention to its parasitism was the case drawn 
in figure 8 of Plate I, where a seedling has attached itself by a 
series of haustoria to another, older Olax plant. 
Nothing definite can be said regarding the preferences of 
Olax roots for particular hosts. The only means available of 
judging was to determine in how far it was easy to collect hausto- 
ria from the plants growing near or with it, a matter depending 
largely on opportunity and locality. In the area from which the 
specimens were obtained, the following have earned the character 
of being favourites :—Albizzia Lebbek, Casuarina equisetifolia, 
Jatropha gossypifolia, Pithecolobium dulce, Pentatropis micro- 
phylla, Dichrostachys cinerea, Azima tetracantha, Cephalandra 
indica and Feronia Elephantum. On the other hand certain 
plants, occurring in fair abundance among the Olaa thickets, 
were searched repeatedly with little success for connections. Such 
were Luphorbia reticulata, Cassia siamea, Melia Azdarachta, 
