Assessment of pollution-control measures in the Kaiapoi River, Canterbury, New Zealand

Improvement of water quality on the basis of biological and chemical assessment is evident in the Upper Kaiapoi River following the installation of a pollution-control plant. A change in the macroinvertebrate community composition, measured using diversity indices, was found to be a useful indicator of the improvement in water quality. The use of legislation to effect an improvement in water quality and reallocation of water resource use is discussed

Park-Williams Number 8 Strain of Corynebacterium diphtheriae

Five clones of the Park-Williams number 8 strain of Corynebacterium diphtheriae, previously maintained in separate laboratories, were examined for their colonial and biochemical properties, for the restriction and modification system which operates to obscure their lysogeny, and for their capacity to produce large amounts of toxin under ordinary laboratory conditions. The phenotypes of their phage, P, produced in strain 603 and C7 (P·603 and P·C7) differ both as to stability to storage in the cold and to inactivation by antiphage serum. Evidence for a high degree of stability in the integration of P prophage in the PW8 genome is presented