Siefert[9] was the first to clearly differentiate the purely endogenetic disorders from those dependent upon a degenerative soil, and evoked exclusively by outside influences. He divided the eighty-seven cases of psychoses in criminals studied by him into two distinct groups, namely, the real psychoses and the degenerative psychoses. Under the former thirty-three cases he places the well-known forms of dementia præcox, epilepsy, paresis, etc. These, according to him, are not in the least influenced by the milieu in which they occur (in this instance, prison environment). His fifty-four cases of degenerative psychoses, on the other hand, were characterized above all by the fact that they stood in the most intimate relation with the environment in which they occurred, and were wholly influenced by the same. The pathologic, degenerative soil which permitted of the development of the psychosis in these individuals consisted of irritability, lability, autochthonous fluctuations of mood, fantastic day-dreaming, a heightened subjectivity to the environment, inability to form correct critical judgment concerning unpleasant occurrences about them and a strong tendency to suggestibility. On the physical side these patients were subject to headaches, migraine, restlessness and anxiety, often associated with disturbances of heart-action, hypochondriacal complaints, and a tendency to become easily tired upon physical or psychic exertion. They also showed, as a rule, intolerance for alcohol, and were wont to react to alcoholism in a strongly pathologic manner. Siefert divides his fifty-four cases of degenerative prison psychoses into the following groups:-- First:--Hysterical degenerative state. These consist of undoubted cases of grave hysteria, with convulsions, physical stigmata, endogenous states of ill-temper, confusional states, Ganser twilight syndromes, etc. Second:--Simple degenerative states. These differ from the preceding group in that hysterical stigmata are wanting. These patients are subject to severe maniacal outbreaks, motor excitements, mutism, attacks of anxious, delirious states, with confusion, etc. Third:--Fantastic degenerative forms. This group concerns markedly degenerated individuals with a pathologically exaggerated imaginative faculty, a strong auto-suggestibility, a tendency to deceit and lying, to inherent fluctuations of mood and hysterical stigmata. On this basis there develop conditions of pseudologia-phantastica, systematized delusional formations of all sorts, delirious psychoses, etc.