(1) States of mental depression (melancholia, psychalgia): (a) Simple melancholia; (b) hypochondriacal melancholia; (c) delusional melancholia; (d) excited melancholia; (e) suicidal and homicidal melancholia.

(2) States of mental exaltation (mania, psychlampsia): (a) Simple mania (folie raisonnante); (b) acute mania; (c) delusional mania; (d) chronic mania.

(3) States of regularly alternating depression and exaltation (folie circulaire, psychorhythm, folie à double forme, circular insanity, periodic mania, recurrent mania).

(4) States of fixed and limited delusion (monomania, monopsychosis): (a) Monomania of pride and grandeur; (b) monomania of unseen agency; (c) monomania of suspicion.

(5) States of mental enfeeblement (dementia, amentia, psychoparesis, congenital imbecility, idiocy): (a) Secondary (ordinary) dementia (following acute or subacute disease, ending in chronicity); (b) primary enfeeblement (imbecility, idiocy, cretinism), the result of deficient brain development or of brain disease in very early life; (c) senile dementia; (d) organic dementia (the result of organic brain disease).

(6) States of mental stupor (stupor, psychocoma): (a) Melancholic stupor (melancholia attonita); (b) anergic stupor (primary dementia, dementia attonita); (c) secondary stupor (transitory, after acute mania).

(7) States of defective inhibition (psychokinesia, hyperkinesia, impulsive insanity, volitional insanity, uncontrollable impulse, insanity without delusion): (a) Homicidal impulse; (b) suicidal impulse; (c) epileptiform impulse; (d) animal impulse; (e) dipsomania; (f) pyromania; (g) kleptomania; (h) moral insanity.

(8) The insane diathesis (psychoneurosis, neurosis insana, neurosis spasmodica).

Some of the German mental pathologists have endeavored to combine in their classification the clinical history with the little that is known of its morbid anatomy. Meynert has gone so far in this direction as to have constructed an ideal mental pathology belonging to the sphere of brilliant speculation rather than exact science. Schüle has well summarized our knowledge on these points, as follows:

I. States of mental defect or degeneration. (1) States of mental defect: (a) Microcephalism; (b) idiocy. (2) States of mental degeneracy, chiefly as the result or further development of (a) Hereditary insanity, impulsive insanity, moral insanity; (b) insanity from the severe neuroses, epileptic insanity, hysterical insanity, hypochondriacal insanity; (c) periodic and circular insanity.