462 SECTIONAL TRANSACTIONS.—M, 
breed true. Results show that high production is not incompatible with high 
fertility and vigour, as is often supposed. Old methods of grading production 
by winter and annual records are inadequate somatically, and misleading 
genetically. All things are possible to a winter-record in early hatchings. 
The system of grading production presented has a double value to the 
practical breeder, because the descriptive somatic gradings, being based on 
the genetic factors concerned, give a line also to the breeding value of the 
bird, for the extreme grades tend to breed true. The grading of winter- 
production by percentages minimises the unequal influences of variable dates 
of hatching. The adoption of this grading system to laying competitions would 
lead to rapid progress in poultry-breeding, and be of educational value to 
poultry-keepers in general, for the winning birds would breed winners with 
more frequency than they do now, and the reasons would be obvious. An 
extension of the laying competitions to 56 weeks or 400 days would extend 
the biological year of the layer to fourteen lunar months, and thus eliminate 
the deep moulters (M birds). The result would be that the 200-egg hen would 
soon be superseded by the 300-egg hen. 
Brown or white egg-mode can be bred true, and broodiness can no doubt 
be eliminated eventually by extended progeny-tests. The large egg-mode, 
which is so important in the Wyandotte, can be bred true by the elimination 
of the N birds of both sexes. The practical proof of the above scheme lies 
in the fact that homozygous strains of EEWWSSmmnnecc birds were 
bred in 1914 at Burbage from the heterozygous birds of the original pedigree 
strains. 
Since the War (1919-21) other pedigree strains and other breeds have been 
tested with success on the basis of the above factorial scheme. 
21. Miss Dororny J. Jackson.—Genus Sitones and its Importance 
in Agriculture. (With Lantern Demonstration and Exhibition 
of Specimens.) 
The genus Sitones belongs to the Curculionide, or weevils, and includes 
several species which are well-known pests of cultivated Leguminose in Europe 
and America. 
Research was commenced in 1918, with the object of discovering which species 
were injurious to leguminous crops in Britain, and the life history of these 
species has been determined. 
The injurious British species may conveniently be divided into two groups ; 
the first group includes those species which breed principally upon peas, beans, 
and tares, and which later migrate to clover and lucerne. ‘lhe most important 
species in this group is Sitones lineatus, l., which in the adult stage causes 
serious damage to the foliage of peas and beans in spring, especially in the 
south of England. In the larval stage it is very destructive to the root-nodules 
of these plants. The second group includes those species which occur upon 
clover throughout the year. Such are S. flavescens, Marsh, puncticollis, Steph., 
sulcifrons, Thun., and hispidulus, F., the latter occurring also on lucerne. 
These species in the adult stage are much less injurious than S. lineatus, but 
in the larval stage are destructive both to the roots and the root-nodules of 
the clover. 
No satisfactory method of control is at present known. In the case of the 
species which breed upon clover, control would be extremely difficult, on 
account of their prolonged period of egg laying, but this difficulty would not 
apply to the species which breed upon peas and beans. Sitones are liable to 
attack by insect and fungus parasites. Thus various species of Braconide 
belonging to the genera Pevilitus, Liophron, and Pygostolus have been bred 
from the adults of several of the injurious Sitones. The fungus Botrytis 
bassiana (Balsamo), Montagne, is common on these beetles, and laboratory 
experiments on. infection with the fungus spores have proved very successful, 
death invariably occurring in nine to thirteen days. 
22. Miss M.S. G. Breeze.—Degeneration in Anthers of Potato. 
The investigation on degeneration in potato anthers described below was 
started four years ago as a necessary accompaniment to plant-breeding experi- 
ments which were undertaken at the same time for economic ends. 
eee 3 ee - > 
