The effect of morphactin sprayed at 0, 0·5, 1·0, 1·5 or 2·0 mg/1 on the concentrations of several nutrients in snapdragons (Antirrhinum, majus L.) were studied under glasshouse conditions. Snapdragon plants treated with morphactin increased in K, and Mg but decreased in Ca, Mn, Cu, Fe, and Zn. Action of morphactin and nutrient element relationships are suggested.

In 1945 we reported (Dick & Bull, 1945) the first observations on the effects of molybdenum in the diet of ruminants in limiting the accumulation of copper in their tissues.

Further observations (Dick, 1952) indicated that there was a third factor which materially altered the control by molybdenum of copper accumulation and this factor, present in lucerne hay, was identified as inorganic sulphate (Dick, 1953a). It was also shown that sulphate regulated molybdenum excretion (Dick, 1953b) in the urine and hence the level of molybdenum in circulating blood (Dick, 1953c).

The duration of the breeding season was studied in 33 Suffolk × Galway ewe lambs which had a mean live weight of 45·9 ± 1·4 kg. The mean dates of onset and cessation of oestrous activity were 8 November ± 1·4 days and 12 January ± 2·6 days, respectively. The mean number of heat periods exhibited was 4·37 0·3 and the duration of the breeding season was 81 ± 5·7 days. Only 18·2 % of animals had ≥ 6 heat periods while 45·5 % of animals had ≤ 3 heat periods. The incidence of silent heats was 9·2 %.

Sulphur deficiency in agricultural crops has never been regarded as a significant problem in Great Britain. However, the widespread use of sulphurfree fertilizers and the introduction of Clean Air Acts together with increased crop yields necessitate a reappraisal of the situation. S.E. Scotland is an area where atmospheric sulphur dioxide levels are considerably lower than most other regions of Britain (Junge, 1972). The concentration of sulphur in precipitation is also relatively low (Stevenson, 1968) and therefore the area is likely to be affected by restricted sulphur supplies. A survey of the sulphur content of soils and corresponding herbage was carried out in this area during 1972 and 1973.

Some misconceptions concerning the application of Griffing's fixed effects model I and mixed effects model B are discussed.