THE entity of serofibrinous pleurisy presents many obstacles to diagnosis. Difficulties are often encountered in the isolation of the Mycobacterium tuberculosis from the sputum, gastric washings and pleural fluid in the tuberculous patient. In addition, aspiration biopsy of pleural fluids frequently yields samples consisting of distorted cells that may not be sufficiently representative pathologically for definitive microscopical diagnosis. Often, specific therapy must be instituted before definitive bacteriologic diagnosis can be established.The purpose of this report is to describe a simple method for needle biopsy of the parietal pleura that may obviate prolonged and costly diagnostic procedures and even, in . . .