268 
The amount of this alkaloid given out by the roots is not incon- 
siderable. Sesamum in its early stages of growth appears to excrete a 
greater amount of material than it builds upon its own substance. ” 
The bearing of these observations on the question of rotation of 
crops is obvious. 
The question may, however, be put why cotton, for instance, 
which grows so feebly near sorghum gvpws at least as well if not 
better, after sorghum than after cotton. From experiments now in 
progress it appears that this is explicable as follows 
When cotton is growing near sorghum the roots of the latter exude 
the toxic substance into the soil in large quantities. This spreads 
rapidly through the soil into the subsoil especially during the rainy 
season, and neighbouring cotton plants are not protected by the fact 
that their tap roots go down far below the zone in which the sorghum 
roots are situated. When cotton follows sorghum, however, the 
condition of affairs is different; the toxic substance remaining, at the 
tune of harvesting, in the roots of the previous sorghum crop is now 
being given out slowly in the course of the decay of these roots * and 
1S „ held entangled m the organic matter of the roots, largely in the zone 
of s°H in which the roots of sorghum spread. Each crop thus fouls 
the soil for a crop of the same variety, whose roots will take the same 
course as a previous crop, more than for a crop whose roots spread in 
another layer of the soil. 
The precipitation of the toxic substance by most of the mineral 
manures, in common use indicates the manner in which many manures 
act in increasing crop yields." 
ACALYPHA FRUTICOSA FORSK. 
This plant is a low shrub, bushy in shape with wiry bran- 
ches, the leaves alternate coriaceous ovate obovate or lanceolate 
narrowed at the base to a short petiole, crenate, blunt, strongly nerved 
quite glabrous 2 to 2 inches long and from i to 1 inch wide. Very 
variable m size and shape They are glandular at the back and aromat- 
ic when rubbed. . The flower spikes are slender yellow and pubes- 
cent, one or two inches long covered with very small male flowers with 
one two or three female flowers at the base. The female flowers are 
enclosed in several three toothed bracts, and are about i inch across. 
Sepals 3 ovate ciliate. Styles strongly fringed and ovary covered with 
long hairs, ft only seems to occur on the east coast of the peninsula 
where I found it at Pekan m open samly spots. Mr. Rostado got it at 
Bundi in Tnnganu and Capt. Macgill sends it from Bagan, Kelantan. 
Rostado gives the name as Te hutan" Capt. Macgill as “ Te’Kampong " 
as opposed to Te Kadai ; and the latter says that the Malays dry the 
leaves and drink the hot infusion like tea as a beverage and also for 
heated body and bowel complaints, and kidney trouble, known as 
Badang panas, Sakit P'rut" and “Ayer Kinching Kuning." 
. - * V ie roots of sorghum and other crops exert an extraordinary 
toxu; effect when mixed with soil in which plants are then grown has been 
proved by the writer in a set of pot experiments.” 
