at intervals). The speed of motion and time of application were varied. All four stimuli produced some instances of negative afterimages of movement. Only the corrugated muslin, however, gave compulsory conditions. With this stimulus (applied longitudinally) it was possible to find a speed and time for each subject at which he reported the after-image on every trial. The stimulus was sometimes removed when the motion stopped and was sometimes allowed to lie stationary against the skin. The latter condition was more favorable to the after-effect. Similar results were obtained on the calf of the leg with one subject. An additional series was performed under compulsory conditions to obtain detailed descriptions of the after-effect. It sometimes appeared cutaneous, sometimes subcutaneous, and sometimes both. In the first case it had a "bright quality and in the second a "dull."

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Benussi's discovery of a tactual illusion of movement produced by the stimulation of separate points in quick succession has been previously corroborated. Recent studies make a more careful introspective study of the illusion. Whitchurch (13) stimulated marked pressure spots using two intensities of stimulus, one that involved only the cutaneous organs and the other both the cutaneous and the subcutaneous. Optimal conditions for the illusion were determined. The distance and the time-interval between the stimuli were the most important factors in conditioning the optimal movement. The illusion involved an integration of quality, time, and cutaneous extent-a pressure diffusing, growing, and extending in time. Andrews' (1) preliminary series was similar to the above but two of his three subjects reported no movement at all. Hence he repeated the stimulation of a pair of spots several times in succession, i.e., gave a rapid alternation of the stimuli for from 5 to 15 alterations. This procedure was designed to strengthen the association between the two spots. The instructions included process as well as "meaning." In this experiment all the subjects reported the illusion. It was variously described as a movement of one member, of both, or as full movement from the first point to the second. The "bow" movement in the air above the skin first described by Benussi was sometimes obtained, especially with one subject. Objective conditions did not seem sufficient for this illusion, the idea of the movement was necessary. In the "bow" movement when the subject attended to the sensations the "bow" disappeared leaving only the discrete pressure. The processes that carried the meaning were visual, kinesthetic, or both.

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Krass describes a number of illusions involving every-day material. A variation of Aristotle's illusion is obtained (6) by rotating the left hand 180 degrees and placing it palm upwards on the table, while the right hand is placed palm downwards upon the left. A key laid along the inner side of both thumbs and moved by the middle finger of the right hand is then felt as two keys joined at the end. With the hands in the same position and the key placed across the hand with the ring on the left thumb and rotated by the forefingers of both hands the apparent rotation is the reverse of the actual. If the flat end of a pencil (4) is pressed on the ball of the finger so that it does not leave its position and the other end of the pencil is moved about, it seems as if the flat end were larger and made of gum. If a glass (5) is held with one hand while the other strokes the rim, the glass seems larger tactually than it does visually. If the inside of the glass is stroked with the ball of the finger it seems smaller.

Johnson's (2) subjects sorted cards that were perforated with four patterns of four holes each. Large goggles with frosted glass were worn so that, as the subject faced a wall he saw a uniform brightness but could, of course, discriminate nothing. In other series the subject wore the same goggles but the room was in darkness. Results were reduced to indicate the percentage of superiority of the performance in card-sorting under the light conditions over the performance under the dark conditions. The results of six subjects showed differences in favor of the light that are significant from the standpoint of probable error, with seven subjects there were slight differences of the same sort, while two others showed a slight, one (an astronomer) a large, difference in favor of the dark condition. The distribution curve of all the differences appears somewhat normal but the mean of the differences is plus 2.09 per cent., i.e., in favor of the light conditions. Johnson concludes that "the inference seems justified that the tactile sensitivity is enhanced by uniform stimulation of the retina by light even though the visual and tactual impressions cannot be referred to the same object and vision cannot serve as a means of orientation."

3. KATZ, D. Psychologische Versuche mit Amputierten. Zsch. f. Psychol., 1920, 85, 83-117.

4. KRASS, M. Ueber eine neue Tasttauschung. Arch. f. d. ges. Psychol., 1918, 37, 300.

5. KRASS, M. Eine neue Tasttauschung. Arch. f. d. ges. Psychol., 1918, 37, 402.

6. KRASS, M. Zwei weiterer Tasttauschungen. Zeits. f. Sinnesphysiologie. 1919, 51, 1-2.

7. LUFKIN, H. M. Cutaneous Localization and the Attribute of Order. Amer. J. of Psychol., 1922, 33, 128-134.

8. PIÉRON, H. De la discrimination spatial des sensations thermiques. Son importance pour la theorie générale de la discrimination cutanée. ..C. r. Soc. de. biol., 1919, 82, 61-65.

9. RUEDIGER, W. C. Local Signature and Sensational Elements. J. of Exper. Psychol., 1921, 4, 469-474.

10. THALMAN, W. A. The After Effect of Movement in the Sense of Touch. Amer. J. and Psychol., 1922, 33, 268-276.

11. TURRO, R. Les origines des représentations de l'espace tactile. J. de psychol., 1920, 17, 769-786, 878-903.

*12. WASSENAAR, T. L'illusion tactile d'Aristote. Arch. neerl. de physiol., 1917, 1, 374-379.

13. WHITCHURCH. A. K. The Illusory Perception of Movement on the Skin. Amer. J. of Psychol., 1921, 32, 472-489.

*14. ZIEHEN, T. Ueber die Abhängigkeit der scheinbaren Grösse taktiler Empfindungen von der Entfernung und von der optischen Einstellung. Zsch. f. Sinnesphysiol., 1918, 50, 79-116.

SPECIAL REVIEWS

J. W. BRIDGES. Outline of Abnormal Psychology. (2d Ed.). Columbus, O.: R. G. Adams, 1921. Pp. 226.

The second edition of Bridges' book comes at a time when popular as well as scientific interest in abnormal psychology has undergone considerable quickening because of the large number of mentally abnormal cases due to war, both soldiers in the army and others in civil life. In the present edition some errors have been corrected, and new material has been added. Blank pages are left for "notes." The second part, "The Mental Syndromes or Symptom-Complexes in Insanity," and the third part, "The Borderline Diseases: Psychoneuroses and Epilepsies," are retained although they are not properly subsumed under the title Abnormal Psychology. These two parts outline the groupings of symptoms, and in some instances the course, the etiology, and the nature of the disease.

Some of the defects of the first edition have been eliminated, references are more frequently given with dates so that editions of books can be determined, typographical errors have been partly corrected, and some definitions have been changed. In a first edition of a work of this character, involving as it does considerable checking and reference, much may be overlooked and criticism of minor points withheld. In a second edition it may reasonably be expected that all gross errors will have been checked, and that some of the lesser ones will be dealt with. In the present work, and the reviewer will confine himself to the part dealing with abnormal psychology, these expectations have not been entirely met.

The effort is made to give the neurological correlates of the abnormalities, which effort leads to absurdities of speculation. This is not decried as a totally bad practice, were it not for the fact that frequently the statements are given in such positive language that the reader is permitted no alternative unless his reading go beyond the limits of the references. The author goes so far as to state that any other explanation "does not relieve one from the necessity of giving an explanation in neurological terms " (p. 31). Synaptic resistances are overworked as explanatory conditions. In one place (p. 82) the changes in synaptic resistance is said to result in systematized amnesia."

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Among matters needing revision or explanation are the following: the second definition of abnormal (p. 9) is a definition of pathological; pathopsychology and psychopathology are not necessarily parts of abnormal psychology (p. 10), they may be its correlates; decreased function (hypo- conditions) are not classified with the absences, increases or perversions (p. 10) but are in a separate group; reference to neurological literature will show that lesion of the primary cortical stations in the post-central convolutions is not accompanied by loss of cutaneous and kinesthetic sensations (p. 24), but by losses of special sensory abilities; the refusal to accept a distinction drawn by Esquirol is not a theory" (p. 26); logorrhea cannot be a verbal hallucination described as "the escape of thought" (p. 28) and at the same time (p. 97) an "extreme garrulity"; there would appear to be no reason in a psychological text for an appeal to teleology (p. 43); in speaking of paradoxia sexualis it is meaningless to say that one form is a premature development beyond the age of the child" (p. 38); it is pedagogically bad, to say the least, to separate two conditions which are conceded to be alike without defining the supposed differences, as in speaking of lower motor neurone" paralyses "and peripheral paralyses" (p. 89); the use of the description "at rest" (p. 91) does not define the conditions in an individual who is trying to maintain his balance on one foot; the invocation of the concept of memory loss to account for functional paralyses (p. 92) and for the aphasias (p. 95) is very questionable and probably gratuitous in view of the recent publications on the latter subject.

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It is advantageous to get the facts clearly presented, and to indicate the possible or probable directions of explanation, but no good purpose is subserved by including meaningless and ill-formed statements. The criticisms are offered as additions and corrections; if space were available more points would be dealt with in the hope that the next edition will far surpass the second.

SHEPHERD IVORY FRANZ

GOVERNMENT HOSPITAL FOR THE INSANE

HENRY H. GODDARD. Psychology of the Normal and Subnormal. New York: Dodd, Mead, 1919. Pp. xxiv + 349.

The hypothetical flow of a postulated neurokyme over an imaginary neuron pattern is the keynote of explanation in Goddard's recent book, The Psychology of the Normal and Subnormal. The