In the past year the literature has been replete with reports stressing the importance of phrenicectomy in the treatment of pulmonary tuberculosis. It has been observed that phrenic neurectomy is not attended with any great danger in man. Lemon,1in a series of experiments on normal dogs, concluded that either unilateral or bilateral phrenicectomy was attended with slight risk and did not produce demonstrable impairment of function in general or of respiratory function in particular. Compensation was sufficient to overcome the loss in function of half or the whole diaphragm of the dog, and the animal was able to carry on its usual activities without embarrassment or dyspnea. Andrus2made studies of the changes in the cardiorespiratory mechanism in dogs, following hemiparalysis of the diaphragm. The experimental data collected were summarized as follows: 1. The pulse and respiratory rates increased about 10 per cent. 2. There was a