Fodrin (formerly designated 26 and 27) comprises two polypeptides (250,000 and 240,000 mol wt) that are axonally transported at a maximum time-averaged velocity of 40 mm/d-slower than the most rapidly moving axonally transported proteins, but faster than at least three additional groups of proteins . In this communication, we report the intracellular distribution of fodrin . Fodrin was purified from guinea pig brain, and a specific antifodrin antibody was produced in rabbit and used to localize fodrin in tissue sections and cultured cells by means of indirect immunofluorescence . Fodrin antigens were highly concentrated in the cortical cytoplasm of neurons and also nonneuronal tissues (e .g., skeletal muscle, uterus, intestinal epithelium) . Their disposition resembles a lining of the cell: hence, the designation fodrin (from Greek fodros, lining) . In cultured fibroblasts, immunofluorescently labeled fodrin antigens were arranged in parallel arrays of bands in the plane of the plasma membrane, possibly reflecting an exclusion of labeled fodrin from some areas occupied by stress fibers. The distribution of fodrin antigens in mouse 3T3 cells transformed with simian virus 40 was more diffuse, indicating that the disposition of fodrin is responsive to altered physiological states of the cell. When mixtures of fodrin and F-actin were centrifuged, fodrin cosedimented with the actin, indicating that these proteins interact in vitro.We conclude that fodrin is a specific component of the cortical cytoplasm of many cells and consider the possibilities : (a) that fodrin may be indirectly attached to the plasma membrane via cortical actin filaments ; (b) that fodrin may be mobile within the cortical cytoplasm and that, in axons, a cortical lining may be in constant motion relative to the internal cytoplasm ; and (c) that fodrin could serve to link other proteins and organelles to a submembrane forcegenerating system .A multitude of proteins synthesized in the cell bodies of neurons are conveyed by the process of axonal transport to the axons and synaptic terminals, which are themselves unable to synthesize most proteins. In the retinal ganglion cells (the centrally projecting neurons of the retina) of mammals and amphibians, the axonally transported proteins can be roughly divided into five groups according to their apparent maximum transport velocities (18,24,38,45,46): the major proteins of the first group (transport velocity > 240 mm/d) are associated with membranous organelles resembling the plasma membrane (26); the second group (velocity = 30-60 mm/d) is heterogeneous and includes mitochondrial proteins and proteins asso-

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Abstract. Meteorological conditions, extremely conducive to fire development and spread in the spring of 1987, resulted in forest fires burning over extremely large areas in the boreal forest zone in northeastern China and the southeastern region of Siberia. The great China fire, one of the largest and most destructive forest fires in recent history, occurred during this period in the Heilongjiang Province of China. Satellite imagery is used to examine the development and areal distribution of 1987 forest fires in this region. Overall trace gas emissions to the atmosphere from these fires are determined using a satellite-derived estimate of area burned in combination with fuel consumption figures and carbon emission ratios for boreal forest fires.

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