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Abstract. The degree of dependence of the growing zone of the Phycomyces sporangiophore upon other parts of the stalk was tested by inhibiting glycolysis and oxidative phosphorylation in the stalk below the growing zone. Initially the growing zone is capable of nearly normal growth when the metabolism in the rest of the stalk is inhibited in this way. However, the growing zone appears to become depleted of something normally supplied from below, because after 3 to 4 hr its growth rate slows down and the growth stops much sooner than in normal sporangiophores. The rest of the sporangiophore appears to have a similar degree of local autonomy because isolated sections from below the growing zone can support protoplasmic streaming for 10 to 20 hr.The sporangiophore of Phycomyces blakesleeanus is an asexual fruiting body composed of a single eelled stalk which supports a sporangium containing numerous spores. The stalk has a 2 to 3 mm growing zone just beneath the sporangium and, at the other end, a "foot" which connects the sporangiophore to the mycelium and allows uptake of nutrients and water. Substrates and subcellular particles are moved up and down the stalk in channels at a rate of about 3 p/sec (11). The stalk has a diameter of about 0.1 mm and can grow to a length of about 10 cm. After the sporangium has matured, the steady state growth rate is about 3 mm/hr. This rate can be temporarily increased by permanent or temporary increases in the intensity of illumination of the growin,g zone, and can be decreased by decreases in the light intensity (12).The aim of this paper is primarily to determine whether the growing zone is dependent upon the rest of the sporangiophore for the substrates and energy necessary for the processes of growth such as cell wall and membrane synthesis. The part of the stalk below the growing zone contains significant quantities of mitochondria, nuclei, and other subcellular particles and might supply the growing zone with substrates. If the growing zone is dependent upon substrates from below, it should have control over the rates of this supply so that they can be adjusted to coincide with ithe varying growth rates. In cells smaller than the sporangiophore of Phycomyces, protoplasmic streaming and diffusion are rapid enough to move substrates throughout the cell in periods comparable to their turnover periods, and thus (8) within the sporangiophore, are respectively 1 sec (13) and 5 sec.[The turnover period for oxygen was calculated from the rate of consumption per sporangiophore which is about 1.0 X 10-9 moles/min (Goodell, in preparation) and assuming that the concentration of dissolved oxygen in the sporangiophore is the same as in distilled water at 200: 0.26 ,umoles/ml (7)]. The time which diffusion takes to move small molecules from one end of a 3 centimeter long sporangiophore to the other can be calculated to be several days on the average, and the time required for streaming to be several hr. [The time required for small molecules to diffuse along the sporangiophore is ba...

Background. Lymphoma presenting with skin involvement has heterogeneous morphology and rarely is seen in children. To study the pathogenesis of this disease, lymphoma cells from a child with B‐cell large cell lymphoma of the skin were cultured in vitro. Methods. Lymphoma cells cultured on a feeder layer under hypoxic conditions grew in vitro after a latency period of 2 weeks. Since interleukin‐6 (IL‐6) induces final differentiation of activated B‐lymphocytes, the cell line was evaluated for the presence of IL‐6 receptors and biologic response to IL‐6. Results. An Epstein–Barr virus (EBV)‐negative cell line (UoC‐B2) was established which expressed CD34, CD45, HLA‐DR, CD19, CD20, sIgM, sIgD, and lambda light chain. Good general concordance was observed between the patient's lymphoma and the cell line by comparing the immunophenotype, genotype, and karyotype. The UoC‐B2 cells expressed surface IgM but did not secrete IgM into the culture media even in the presence of supplemental IL‐6. Conclusions. A B‐lymphoid cell line (UoC‐B2) was established from a child with primary cutaneous lymphoma. The cells expressed cell surface IgM and receptors for IL‐6 but supplemental IL‐6 had no effect on IgM production or cell proliferation.

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On the other hand I have a specimen I obtained at a post-mortem examination I held on Mr. E. P., age 72 years, in which I was assisted by Dr. J. Harvey Craig, of Mansfield, O., which you will •observe is an old, irreducible inguinal hernia, in which the sac has become enormously thickened and attached in many places to the loop of intes¬