1919] 
New Zealand Institute Science Congress. 
279 
Portobello had decided to start with the common sole and liberate a large number of 
marked fish. Referring to the liberation of turbot, it was hoped—with luck—to 
observe some result in about seven years. The liberation of English crabs and lobsters 
had been carried out, but so far no results had been observed. 
Plant-breeding Methods and some Results, by F. W. Hilgendorf. 
Press Notice (Lyttelton Times). 
Dr. E. W. Hilgendorf read a paper on plant-breeding, the methods followed, and 
some of the results. The paper gave a general basis for the system most likely to afford 
satisfactory results in the breeding of self-fertilized plants, such as wheat and oats. 
The theories of heredity propounded by Darwin, Gaiton, de Vries, Weismann, Johansen, 
and Mendel were contrasted, and those parts of Weismann’s theory which postulated 
the improbability of variation in the offspring of animals and plants developing without 
a paternal parent were adopted by the author. The theory was extended to embrace 
the usual non-variability of self-fertilized plants, and a large number of experiments 
from all over the world were quoted to show that there had been no result from 
selecting among plants that were all descended from a single seed of a self-fertilized 
plant. For instance, the tallest plants descended from a single grain of wheat were 
selected out each year for thirteen years. The average height of the offspring during 
the first five years was 2'67 ft., and during the last five years 2\34 ft. In the case of 
College Hunter’s, which was bred up from a single seed selected at Lincoln College in 
1910, and whose offspring now covered thousands of acres in Canterbury, no single 
case of hereditary variation had been found. The only case tending to display variation 
within a pure line was that of the Australian wheat called Federation ; but here the 
experimenters were dealing with a wheat that was certainly crossbred, and not with a 
pure line at all. 
The author concluded that, though variation in a pure line must certainly occur 
by mutation, such occurrences must be too rare to form a basis for practical improve¬ 
ments in plants, and stated that the object of his paper was to discourage any attempts 
in that direction. Such work was based on the false analogy of animal-breeding, 
which must depend on cumulative selection, because of the bi-parental origin of the 
offspring. 
The second part of the paper consisted in the display of some results obtained 
at Lincoln College in the improvement of the common Canterbury wheats; increased 
yields had been obtained from pure strains of Hunter’s, Solid-straw Tuscan, Purple - 
straw Tuscan, and true Pearl, and the progeny of all of those was now being grown 
on Canterbury farms with generally satisfactory results. 
The Control of Succession in Surface-sown Grassland, by A. H. Cockayne. 
Press Notice (The Press). 
Mr. A. H. Cockayne read a paper, which was illustrated by an interesting series 
of lantern-slides, on “ The Control of Succession on Grasslands,” which he characterized 
as one of the most important of our pasture problems. Over large areas of the surface- 
sown grassland of the North Island great changes in the composition of the vegetation 
occurred before a state of equilibrium obtained, and in many cases the transitional 
successions might be of grave objection. The methods adopted for the avoidance of 
these objectionable successions were not always successful, as many thousands of ruined 
bush burns could testify. Whether the main cause of the failures to direct successions 
along the lines productive of permanently profitable grassland lay in errors of seeding 
or errors of management was a matter requiring the most careful investigation and 
study. 
Compatibility of Spraying-mixtures, by W. C. Morris. 
(This paper will appear in the N.Z. Journal of Agriculture.) 
Nitrification in Relation to the Calcium-carbonate Content of Canter¬ 
bury Plains Soils, by L. J. Wild. 
Abstract. 
The work necessary to the completion of this paper was interrupted at a 
critical time by an attack of pneumonic influenza. The problem may be 
