In an article entitled "A Method of Decerebration,"1we described the technic of producing decerebrate preparations by rendering certain parts of the nervous system anemic. Briefly, this consisted of ligature of the basilar and carotid arteries. In this way that part of the brain cephalad to the ligature on the basilar artery may be made anemic. Such an occlusion of blood supply after fifteen minutes destroys the function of the anemic part permanently. By varying the level of the ligature on the basilar artery, various levels of decerebration can be obtained. It was pointed out that the method produced relatively sharply defined borders between normal and anemic or functionless parts, and therefore the study of function of certain levels of the central nervous system could be more accurately made. Former methods of decerebration were mutilating in character and produced immeasurable degrees of injury about the level of the decerebration.