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Clover Case-moth (Coleophora spissicornis).—This is an introduced insect which is a serious pest of red clover in Denmark. It occurs in both Islands of New Zealand, where it damages the florets of white clover at North Auckland, Hastings, Blenheim, and Ashburton. Similar injury to red clover at Ashburton and in South Canterbury is possibly due to this insect. The insect has been studied and an account of the woi'k has been prepared. Tobacco-store Insects. —Attention has been given to the control of moths infesting stored tobacco. Argentine Wheat-weevil (Hyperodes griseus).—Owing to Ihe importance of this insect in the wheat-growing areas of New Zealand, an endeavour is being made to locate parasites of this weevil in the Argentine. The insect occurs there, but is not known to be destructive. Linen Flax.—The possibility of plant bugs having a detrimental influence upon linen flax led to a preliminary study of the position. There are indications that certain species of plant bugs possibly attack the seeds. A watch has also been kept upon the leaf-mining lly (Phytomyza atricofnis), which is extremely abundant in New Zealand and is known to mine linen plants in other countries. In view of the occurrence of a. mite ( Tyroglyphus farinm) amongst flax-seed, an investigation, in conjunction with the Agronomy Division, is being made into the influence of this mite upon flax-seed under varying conditions* of temperature and humidity. Termite Research,—See Timber Protection Research Report, p. 25. GRASSLANDS DIVISION, PALMERSTON NORTH Director: Mr. E. Bruce Levy General Plant Breeding and Pedigree-seed Production,—The plant-breeding work of the Division is fundamental to the maintenance and improvement of the standard of pedigree seeds of pasture species, and as far as possible, therefore, with the reduced staff available, the volume and scope of the plant-breeding work has been maintained. The short- or longrotation type of pasture offers great possibilities in any scheme of rapid increase of pastoral production, and the policy of the Division has therefore been to breed strains of pasture plants for a rotational type of farming as well as maintaining and improving the strains bred for truly permanent pastures. Breeding is being carried out with the following pasture cocksfoot species: Perennial rye-grass, Italian rye-grass, short-rotation rye-grass, timothy, white clover, broad red clover, and Montgomery red clover. Blind-seed Disease of liye-grass.—The possibility of breeding a line less susceptible to the disease than the strains at present available is being studied. A series of crosses with resistant and susceptible plants has been made, and this season some five hundred of the progeny plants have been inoculated with spores of the disease in an attempt to obtain information in the inheritance of resistance and susceptibility. Short-rotation Rye-grass.—A new glasshouse isolation has been made of a type which has shown great promise under trial. Seventeen bushels of nucleus seed of this type have been harvested at Palmerston North and 84 bushels at the Agronomy Division. Breedingwork is being continued with this type and with various other types obtained by hybridization of perennial and Italian rye-grass. Cyanogenesis in White Clover. —The mode of inheritance of cyanogenesis in white clover has been determined. From this information two strains of white clover have been bred, the first exceptionally high in the cyanogenetic glucoside, and the other free from the glucoside. Areas of these two strains have been planted and after harvesting will be used for. feeding trials. Vegetable-production.—Variety trials of the more common vegetables have been made and quantities of each produced for the dehydration of vegetable work by the Chemical Laboratory. Strain-testing Grasslands Substation, Lincoln,—Testing of selected strains is continuing at Lincoln, and a further series of grass plots, tiller rows, and single plants were spring sown. A further trial comparing subterranean-clover types will be established this autumn. Trials in Great Britain. —Following on the establishment of field trials of New Zealand seed in Great Britain, bulk supplies of the following species have been forwarded for additional trials: Perennial, Italian, and short-rotation rye-grass; cocksfoot; timothy and broad red; Montgomery red and white clovers. In addition, a comprehensive range of New Zealand seeds have been forwarded for plot trials. Field Ecology The trial on the effect of animal excrements on pasture growth has been continued, and results continue to show the importance of a complete and intelligent use of this valuable material. There is also consistent evidence of the great value of the improved strain of white clover used in this trial. Production on the paddock on which no return of either dung or urine is made has increased in the last year. This has been mainly due to the clover content holding up; but there has also been much better growth of the grass, most probably because of the nitrogen secretions into the soil from the clover bacteria.

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