Ally in Relation To

relations and friends. Conversely, insane conduct may be properly testified by a relation, but fail to be displayed when under observation in an institution. The medical evidence then will probably be that of mental deficiency. In such case the witness must balance the relative merits of hearsay statements and personal observation. Mental defect mnay be simulated by mental dullness resulting frotn physical disabilities such as anaemia, chronic intoxications, the sequelke of debilitatinig diseases or head injuries, upon bad sex habits, privations, fatigue or too rapid growth. But a physical cause of mental dullness may aggravate mental defectiveness, and a full physical as well as complete mental examination is necessary for accurate diagnosis. Since the indications of mental deficiency are the. negationi of those of efficiency, it follows that the intermediate group between the defective anid norm'al, namely, the subnormals, will present symptoms of an indeterminate character. The line of demarcation between the normal and subnormal is of comparatively slight importance forensically, buLt that between the defective and subnormal is of immediate concern to the psychiatrist. In differentiating between them the medical man must be guided by the definitions of mental defectiveness laid down in the Act of I927, by his knowledge and experience of normal initelligence, of normal mental capacities and reactions, and of conIduct which is normal in the environiment from which the subject is drawn.