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The use of polyester fibers has grown more rapidly than that of any other man-made fiber. Many factors have contributed to this growth. Polyester's unique physical properties of strength, high modulus, elasticity, and durability are the basis for its success. The tailorability of the fiber makes it possible to generate a whole family of property variants for a wide variety of end uses. The ready availability and low cost of the raw materials, the continuing advances in polymerization technology, and the versatility of the melt spinning process have also been major factors in establishing polyester as the leading man-made fiber. New end uses have had a major impact on the growth of polyester. Most notable was the introduction of durable press fabrics for clothing and home furnishings. The consumer preference for easy-care fabrics and garments makes the durable press area one of continuing growth. Two relatively new areas where growth is expected to continue at a rapid rate are tire cord and textured knits for women's and men's outerwear.

Fifty strains of Staphylococcus pyogenes were tested for ;coagulase' by the slide method using plasma, serum, and plasmas rendered fibrinogen-free by various methods. It was found that the organisms were clumped by all these reagents. The significance of these findings is discussed.

The effect of the presence of carbohydrates on the pigmentation of Staphylococcus aureus was investigated. It was shown that pigmentation is greatly increased in the presence of those carbohydrates which are fermented by the organism. This effect may be due to the products of fermentation.

The ultrastructure of sectioned cells of mutant and wild type Rhodopseudomonas spheroides has been examined by electron microscopy. The characteristic vesicles associated with the presence of bacteriochlorophyll were found in wild type cells grown with low aeration. These were also found in mutant TA-R which forms bacteriochlorophyll under high aeration. None of the mutants with blocks in bacteriochlorophyll synthesis contained intracytoplasmic membrane. These included mutant 8-17 which accumulates bacteriochlorophyllide but fails at the phytolation step. We conclude that the intact bacteriochlorophyll molecule, or some particular membrane protein associated with it, is needed for the development of the characteristic intracytoplasmic membrane system in R. spheroides.

Phytol has been separated and identified in the unsaponifiable lipid fraction from wild type Rhodopseudomonas spheroides, but it was not detected in mutant strains blocked at various stages of bacteriochlorophyll synthesis. Incorporation of (14)C-acetate into phytol paralleled bacteriochlorophyll synthesis in suspensions of the wild type incubated anaerobically in the light. The addition of chloramphenicol inhibited both processes. It is concluded that phytol formation is tightly coupled to the synthesis of the pyrrole component of bacteriochlorophyll.