With the exception of Kirby, whose work has already been discussed in the introduction, we have been able to find only one author who has attempted any symptomatic discrimination of the recoverable and malignant catatonic states. Raecke[29] made a statistical study and found that 15.8% recovered, 10.8% improved, 54.4% remained in institutions, while 30% died. With the etiology mainly exogenous 20% recovered and 14.3% improved. A good outcome was seen in 30.2% of hereditary cases, while only 22.7% did well in the non-hereditary group. His most important contribution is in his formulation of good and bad symptoms. He thinks that dull, apathetic behavior with uncleanliness and loss of shame are not so unfavorable as has been thought. Malignant symptoms are grimacing with prolonged negativism but without essential affect anomaly, decided echopraxia and echolalia and protracted catalepsy. We would agree with this, although command automatisms have not been prominent either in our benign or malignant stupors. Two writers have made special observations that should be confirmed and amplified before their significance can be established. Whitwell[30] thinks that in addition to a diminished activity of the heart there exists a pathological tension. Ziehen says that he also has frequently seen angiospastic pulse-curves in exhaustion stupor or acute dementia, but that other pulse pictures may be seen as well. Any such studies should be correlated rigorously with the clinical states before they can have any meaning. Wetzel[31] tested the psychogalvanic reflex in stupors and in normal persons who simulated stupors. He found them different. Only one publication has come to our attention in which an attempt is made at psychological interpretation of various symptoms in stupor. Vogt[32] derives much from a restriction of the field of consciousness. Only one idea is present at a time, hence there is no inhibition and impulsiveness occurs. Similarly, if the idea appear from without, it, too, is not inhibited, which produces the suggestibility that in turn accounts for catalepsy. Stereotypy and perseveration are other evidences of this narrowness of thought content. Negativism is a state, he says, of perseverated muscular tension. [This would apply only to muscular rigidity.] So far as it goes, this view seems sound. Of course it leaves the problem at that interesting point, Why the restriction of consciousness?