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Fabric Pest Investigation.—ln testing the moth-proofing efficiency of certain materials some interesting anomalous results were obtained that suggest inhibition of moth-proofing activity of these materials when applied under certain conditions. A test method was devised for assessing moth-proofing efficiency of chemically treated fabrics under standard conditions. Brief observations were made on the ability of clothes-moth and carpet-beetle larvae to survive without food. Some larvae of the Australian carpet beetle (Anthrenocerus australis (Hope)) survived 335 days without food. Investigation of Resistance of Plants to Insects.—An investigation of plant resistance to insects has been commenced, the first subjects selected for study being varietal resistance of swedes to aphids and of carrots to aphids and rustfly. Mite Investigations.—A special investigation of both the Tetranychid and Eriophyid mites is in progress. The taxonomy, biology, economic importance and control are being studied. Several mites of economic importance have been discovered during the past year. Specimens for Identification.-—During the year approximately 530 specimens were received from Orchard and Fields Instructors of the Department of Agriculture and from farmers and market gardeners for identification of disease and advice on control measures. Publications.—Twenty-eight technical papers were prepared by the staff and submitted for publication. During the year the bulletin on tomato diseases and pests was published, and a revised " List of Plant Diseases in New Zealand " was completed and submitted for publication. The manuscript of a monograph on the " Aphids of New Zealand" has also been prepared and is awaiting printing. SEISMOLOGICAL OBSERVATORY Director: Mr. R. C. Hayes SEISMOLOGY Summary of Seismic Activity in New Zealand in 1949. —In 1949 the greatest number of felt earthquakes were recorded in February; and one of the strongest shocks of the year occurred on 10th February, at a depth of 170 km. (105 miles), off the coast of South Taranaki. The highest intensities in this shock affected the Taihape-Wanganui area, and it was perceptible from Tolaga Bay to South Canterbury. Although the remainder of the year was comparatively quiet, a shock of intensity M-M VI occurred in the southern part of the South Island on 27th May; and one of intensity V-VI occurred between Murchison and Hanmer on 28th September. A certain amount of activity persisted in the latter region throughout most of the year. Intensity V was experienced at Karamea on 23rd December. On 27th June a shock in the White Island region occurred at a depth of 330 km. (205 miles), and this depth is second only to that of a shock in the same region on 27th June, 1942, at a depth of 370 km. (230 miles). Outside the main seismic zone, some minor activity occurred in the Great Barrier Island, Ruawai (Northland), Paeroa, and Raglan regions. Shocks located in unusual regions occurred on 14th April and 27th May, from 100 to 200 miles east of Christchurch; and on 16th September, west of Cape Egmont. In all, 97 shocks were reported felt during the year; 71 in the North Island, 34 in the South Island, and Bin both Islands. The maximum intensity reported in both Islands was M-M VI.

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