4.92 SECTIONAL TRANSACTIONS.—K, K*. 
seedling plants, the identities of which were afterwards confirmed while in the 
flowering stages. The results of this research have been extremely illuminating. 
The chromosome complements have been classified according to size, number 
and shape of the constituent chromosomes, occurrence of satellites, position of 
constrictions and incidence of fragmentation. There are probably two distinct 
polyploid series, one in which the haploid numbers are 6, 9, 12, 15, 18, 21, 24 and 36, 
and one in which the numbers 10 and 20 occur. Two species have been examined, 
E. segetalis var. portlandica and E. fetica, in which the diploid number is 16. 
Dr. J. Larrer.—Meiosis in Lathyrus. 
DEPARTMENT OF FORESTRY (K*) 
Thursday, September 24. 
Discussion on Wood Preservation :— 
(1) Mr. R. §. Pearson, C.I.E.— Research in Wood Preservation. 
A brief review is given of the different lines of approach necessary to investigate 
the problem of prolonging the life of timber by antiseptic treatment and of controlling 
the attack on timber by either fungi or insects. Stress is laid on the necessity of 
co-ordinating research work carried out by the different groups of investigators, 
without which the results cannot claim to have been based on sound scientific 
principles. A short review is given as to the means of obtaining co-operation between 
investigators in Wood Preservation, Chemistry, Entomology, Mycology and Utilisa- 
tion, when studying the subject of ‘ Preservation and Control of Damage to Timber.’ 
(2) Mr. K. Sr. G. Cartwricut.—Toaicity of Preservatives against 
Wood-destroying Fungi. 
After giving a short general account of the damage to timber caused by fungus 
decay and the increased importance of wood preservation owing to the shortage of 
the world’s timber supplies, some of the methods used for the testing of the relative 
value of different wood preservatives in the laboratory are described. 
The comparative value of tests on an artificial medium and on wood blocks is 
discussed. 
The necessity of amplifying laboratory tests by service or large-scale ones is 
emphasised, and the paper concludes by indicating other lines of research on which 
wood preservation may develop. 
(3) Dr. R. C. Fisnzr.—Prevention and Control of Damage by Wood- 
Boring Insects. 
Damage by insects to structural and manufactured timber in this country is of 
three distinct types dependent upon the insects causing it. There is the damage 
caused by longhorn beetles and pinhole borers, both groups essentially forest insects ; 
there is the damage caused by powder-post beetles occurring in partly seasoned and 
recently seasoned hardwoods, and finally there is the type of injury for which the 
death-watch beetle and its allies, the furniture beetles, are responsible in long-matured 
and old timber. The paper describes the occurrence of these different types of insects 
in timber at different stages in its utilisation and discusses the food relations of the 
insects at each stage. The development of preventive and control measures based 
on a knowledge of the biology of the insects is then described, and the use of wood 
preservatives and insecticides against wood-borers in this country is also discussed. 
Particular attention is devoted to the problem presented by the death-watch 
beetle. Although a number of palliative measures are available against this insect, 
knowledge of the details of its life-history and ecology are lacking. It is pointed 
out that the acquisition of fuller knowledge of the biology and physiology of the 
death-watch beetle is the most hopeful contribution which can be made towards 
the solution of this problem, and will afford a sound basis for the application of 
improved control measures. 
