TRANSACTIONS OF SECTION K. 797 
grain, was not so where the form of the ear was concerned. So far as has been 
observed, there is likelihood of the white forms of the series conforming to theory 
by continuing to produce white (recessive) ones only. It remains to be seen 
whether the black forms will vary in the manner required by Mendel and produce 
a stated proportion of white ones. 
4, The Clover Mystery : a Probable Solution. 
By Rosert H. Exxior. 
The great uncertainty of the clover crop is noted. The following experiment 
throws light on the most common cause of failure. 
One half of a field was sown with a mixture of grasses and clovers purchased 
locally, and the other half with a similar mixture bought from an English seeds- 
man. On both halves the clover plant was equally good after harvest, but by the 
following spring every plant from the seed locally supplied failed, while the clover 
from the English seedsman was still vigorous. Reasons are given to show that 
such a total failure after the clover has successfully come up must be owing to 
the seed having been obtained from an unsuitable climate. 
Where the failures are partial it is shown that these are mainly owing to the 
presence of rye grass, and partly to six minor contributory causes, the details of 
which are given. 
For the most economical and uniformly successful growth of the fullest clover 
crops three things are mainly necessary: (1) seed from a suitable climate; 
(2) land deeply supplied with humus, and deeply tilled, with the agency of 
the system pursued at the Clifton-on-Bowmont demonstration and experimental 
farm; and (3) the exclusion of perennial rye grass, or its use in small degree. 
With these conditions and general good management an increase of at least 
25 per cent. may be obtained over crops grown under ordinary circumstances, and 
that, too, without any manure being used excepting, perhaps, some artificials with 
the turnip crops of the rotation, Evidences from an upwards of twenty-five years’ 
experience on a large scale are given to show that if rye grass is excluded, or 
used in small proportion, and suitable clover seed sown, fair crops of clover can 
be generally relied on, and that the extensive failures that often occur are owing 
partly to the seedsman and partly to the farmer. 
Evidences are given to show that the failure of crops generally, and especially 
from over-wet or over-dry seasons, is mainly owing to humus deficiency in the 
soil. 
FRIDAY, AUGUST 19. 
The following Papers were read :— 
1. On the Problems of Ecology. By Professor A. G. Tanstey, U/.A., F.L.S. 
Ecology may be defined as the study of those relations of plants to their environ- 
ment dependent on geographical and topographical factors. The author pointed 
out that the diversity of vegetation on the earth’s surface is an ordered diversity, 
in which aggregates can be distinguished owing to definite, though often extremely 
complex, causes. It is very largely with topographical aggregates, due to soil, 
water, and other local conditions, that ecology has to do. The study of these 
topographical aggregates, or plant-associations, falls into two parts, corresponding 
with the two necessary stages of all scientific investigation, the descriptive and 
the experimental. It was shown that the first of these, which largely takes the 
form of ecological survey and the construction of maps of vegetation, is both a 
necessary and a valuable part of the study, since problems are revealed, and their 
solution often indicated at least, in the course of field-work, which would not be 
suspected by the experimenter in his laboratory and garden. Attention was 
called to the danger of wasting time and energy over trifling features, and was 
