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19 October 1973
Vol 182, Issue 4109

About The Cover

Photomicorph (Nomarkski interference microscope ) of 18 neurosecretory cells from the pars intercerebralis of the brain of an adult cockroach (Periplaneata americana) after 3 weeks of culture in a achemically defined medium. Nerve fibers of a considerably large size branch out profusely from the neurosecretory cells and make multiple ineterconnections (about X 640). See page 291. [K. R. Seshan and R. Levi-Montalcini, Washington University. St. Louis, Misssouri]