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Linen Flax. —The work of this Division lias so far been confined to anatomical studies. This work has so far shown (i) that there was very little difference amongst the flax from the mammal trials (however, the flax from the different treatments was placed in the same order as it was in the Lincoln fibre analysis, which also showed differences that were hardly significant); (ii) no effect from oversowing with potash; (iii) certain differences due to soil types; (iv) that differences between flax grown after turnips and after lea may be very striking; (v) in one case a crop manured with blood and bone had much more heavily lignifled fibres than the corresponding crop without blood and bone. Fibrous Plaster.—A number of species have been tested, with emphasis on grasses and sedges, since this material does not require decortication. NasseUa leaf proved excellent and combined well with linen-flax tow. It has the advantage of an existing large source of supply, but there is only a limited period during which the leaf can be collected without danger of spreading the weed by seed caught up in the leaves. Further work has therefore been postponed. Preliminary tests of cabbage-tree leaf (Cordyline austraMs) showed great promise, and a bulk lot will be prepared for a thorough try-out. Hie fibre is sufficiently promising for certain types of work to merit detailed research on the various questions involved in bringing it into commercial production. Weeds Hard Fern.—From the study of the significance of spores in hard-fern infestations (N.Z. Jo-ur. Sci. & Tech., 23, 113b-125b) it has been concluded that (i) many areas if once thoroughly cleared of hard fern could be kept permanently free of the weed; (ii) on colder slopes in high-rainfall areas where a close sward of grass cannot economically be maintained re infestation is inevitable after even the most thorough, elimination, and here afforestation is recommended. dorse. —An experiment with wheat indicated that a gorse cover definitely increases soil fertility. Germination of seed was found to be fairly uniform throughout the year. Seedlings develop a taproot about 5 ft. long in six months if water-table conditions are suitable, with good production of nodules to 3 ft. Plants in which the crown had been grubbed right out showed no regrowth; with the crown chipped at ground-level strong regrowth occurs. Stem cuttings root readily, but no growth was obtained from rootcuttings, either in the field or in the glasshouse. General field studies have been continued. Nassella— Field-work during the year revealed increasing density of infestation in the infected areas, and in Marlborough considerable spread to previously non-infected areas. Experimentally-grown tussocks eleven to fifteen months old flowered and gave high yields of seed, some of the older plants producing over twelve hundred inflorescences in two crops, one after complete defoliation). Regrowth after cutting is rapid, of the order of -J in. to 1 in. in twenty-four hours. Seed in soil was still germinating after nine months. Extensive germination trials are under way. Seeds treated with a wide range of chemical weed-killers indicate that such treatment accelerates permeability to water of the husk and promotes germination. Tussock-grassland Tussock areas were examined at Mount Kurow, Te Akatarewa (Waitaki Valley), Mount Meyer, Hunter's Hills, Cass, Molesworth, and Tamdalc. Special attention was paid to selecting areas for observational and experimental work on improvement of cover and erosion control. Taxonomy Work lias been continued on the seeds of legumes, weeds, and indigenous species, and many illustrations have been completed preparatory to the issue of bulletins covering these projects. The major genera under revision are Actum (for biological control work, and as agents of erosion control) and Catula (with special reference to species useful as material for surgical dressings). General taxonomic work is being done on the Gramince, Cyperaceffi, Conifer'®, and marine alga;. Much other incidental taxonomic work is in progress, including revisions of the weed species of needle-grass and oxalis. Ecology Ecological work in hand, to be presented as papers, bulletins, or books, covers the topics distribution of marine alga;, the plant covering of the Wellington District, the vegetation of New Zealand, the influence of climatic factors on vegetative cover and distribution, vegetative aspects of erosion in the Orongorongo area, and polymorphy in indigenous species. Much ecological work is, of course, involved in the projects dealt with under other heads. Miscellaneous Of the miscellaneous projects in hand the following may receive brief mention. Teasel: Growth has been good, and sufficient heads for a thorough test should be available. Viper's Bugloss (" Blue Borage," EcMum vulgare) : Material from Marlborough was forwarded to the Wallaceville Laboratory. No ill effects were observed in sheep during the feeding trial. Lampe's Mallow: Sufficient seed has been harvested to provide material for a feeding test of this forage plant. Sweet Brier (Rosa rubiginosa): Surveys have been made for the localities where hips can be obtained in quantity for vitamin-supply purposes,

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