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Summary: Populations of heterotrophic bacteria occurring on healthy green leaves of Lolium perenne were estimated using a dilution technique. Bacterial populations in spring and summer were relatively low compared with counts obtained in September when the highest maximum and monthly mean air temperature was recorded. The area of leaf surface colonized rose from about 0·0001 % in May to approximately 0·1 % in September. Over 600 isolates were examined and most found to be Gram-negative and chromogenic. The bacterial populations consisted of only a few taxa and the variations in total numbers were due to changes in the relative abundance of these. The predominant flora were identified to the genera Chromobacterium, Corynebacterium, Pseudomonas and Xanthomonas. Leaf impression and overpour techniques gave some indication of the micro-ecology of bacteria on the leaf, and showed the presence of actinomycetes which were rarely observed on dilution plates.

In his article in the January issue (Vol 2 No 1) John Wellens offered for consideration the view that Job Analysis can be death to the concept of creating a situation in which the subordinate manager can optimise his contribution through the exercise of initiative and decision‐making, that it is restrictive and inward looking, and is not the core activity of management training. These are powerful criticisms that must not be allowed to pass without comment, especially when so many newly‐trained training officers will have accepted this concept on the courses they attended, and may therefore feel completely confused. My own personal philosophy and strategy of management training, education and development is based on the job analysis concept, which does, however, vary from that put forward by John Wellens.

An experimental investigation of the spins of the 2.14 (Jɪ) and 5.03 (J) Mev levels in B¹¹ has been made using the B¹º(dp)B¹¹ reaction to populate the 5.03 Mev level in B¹¹ and then studying pɣ and pɣɣ angular correlations to determine the values of J and Jɪ . The theoretical analysis of the angular correlation data is based on a method in which the dp reaction mechanism is represented by a relatively small number of experimentally determined parameters and therefore the resulting spin assignments are not open to the usual criticisms of the use of (sometimes doubtful) nuclear reaction theories for the positive determination of nuclear spins. Using the information gained from this experiment and previous experimental information on the statistical distribution of M1 to E2 multipole mixing ratios it was possible to assign an overwhelming statistical probability in favour of the J = ³⁄₂, Jɪ = ½ spin assignment. These spin assignments are in agreement with previous tentative ones and with the theoretical shell model calculations of Cohen and Kurath. The parameters, determined by this experiment, describing the dp reaction are compared with those calculated using stripping theory and are shown to be in disagreement with both the Butler Plane Wave and Distorted Wave Born approximation calculations.

An experimental method for the detection of the d(D,ɣ)He⁴ reaction has been developed. It involves the use of a double focusing magnetic spectrometer in conjunction with a solid state counter mounted in the focal plane of the spectrometer, the counter determining both the energy and dE/dx of the incident particles from the reaction. The design and construction of a particle beam handling system to guide the particle beam from the Van de Graaff generator to the object point of the spectrometer has been completed and tested. Using this beam, the characteristics of the spectrometer and solid state counter have been determined and recorded. An attempt was made to detect the d(D,ɣ)He⁴ reaction but no directly useful information on the reaction crossection was obtained. However, utilizing the knowledge gained during this experiment, it should be possible to make a more exacting attempt at the reaction crossection determination.