Needle biopsy of the pleura1was first used after it was shown by Small2and others3that open biopsy of the pleura was often a good indicator of underlying pulmonary disease. In expert hands the use of the Vim-Silverman needle has produced some very gratifying results. It has, however, two disadvantages: 1. A pleural specimen is often not obtained. 2. There is a danger of boring out a core of lung, especially when there is only a very thin cushion of pleural fluid. In an attempt to overcome these difficulties, I have designed an instrument. Its most important unit is a curet-like needle, which has a side slot shaped as in figure 1 C and is set 2 to 3 mm. from the terminal blunt end; the blunt tip is closed except for a small central hole which allows, if necessary, a small needle to push out