562 PHILOSOPHICAL PERIODICALS. ' Die Precision der Blickbewegung und der Localisation an der Netzhaut- peripherie.' [The error of localisation increases with increase of the distance of the point of stimulation from the centre of the retina. In localising an object in the feld of vision, we incline to bring it too near the fixation-point of the primary position.] W. Uhthoff. ' Ein Beitrag- zur congenitalen totalen Farnbenblindheit.' [Central acuity of vision 1/5-1/6 of the normal. Konig's foveal scotoma found. Relation of lateral to central vision dependent on illumination. Nystagmus, corre- sponding to extent of scotoma. Ophthalmoscopic status normal. Changes of central acuity of vision with intensive change of illumination furnish a general confirmation of the results of Konig and Pfluger. Stimulus-limen of light sense approximately normal ; macular limen higher than eccentric (Hess and Hering). Sensible discrimination a function of intensity of illumination (Hess and Hering). Dark -adaptation quicker than normal. Colour-sense as described by previous observers. Bed end of spectrum curtailed ; violet not. Maximal brightness in green of 580 JJL. Bering's view of white and coloured valence of colours con- firmed by comparisons with the normal eye.] W. von. Zchender. ' Die Form des Himmelsgewolbes und das Grossererscheinen der Ges- tirne am Horizont.' [The watch-glass form of the heavens is not a matter of direct observation, but a traditional doctrine. Acute angles, horizontally directed, are underestimated ; vertically directed, over- estimated. Hence the overestimation of the moon at the horizon, and the supposed watch-glass form of the sky. Both are referable to Volkman's law of the apparent divergence of two vertical parallels. The spherical form of the sky is really better founded than the watch-glass form.] Besprechung. [Martinak on Erdmann, Dodge and Huey (psychology of reading).] Literaturbericht. Vol. xx., Heft 6. W. Sternberg. ' Geschmack und Chemismus.' [The only two tastes, in the strict sense, are sweet and bitter. All other ' tastes ' are compounds of taste and touch. Bitter makes us hungry, sweet makes us thirsty. In spite of the diametrical difference for sensation, the molecules of sweet and bitter are very closely related, and are easily transformed the one into the other ; a proof of the delicacy of the organ, and a fact of teleological significance.] O. Abraham und K. L. Schaefer. ' Ueber die maximale Geschwindigkeit von Tonfolgen.' [Siren experiments. From contra-octave to fourth accented-octave the trill (tremolo) limen is given with a tonal duration of about 30 or ; the musical interval employed is unimportant. A musical figure can be rightly cognised when the duration of the separate tones is about 100 a.] O. Abraham. 'Ueber das Abklingen von Tonempfindungen.' [We hear a trill (tremolo) when the time of fall is negligible in relation to the duration of the tones, and a rough clang when the time of fall is too long. The foregoing experi- ments show that the time of fall is the same for all tones, irrespective of pitch. Mayer's results to the contrary are explicable from the principles that a sufficiently large fluctuation of intensity means the inaudibility of the weaker tone, and that high tones are psychologically more intensive than low tones of the same objective strength. Musical experience is explained by resonance and physical after-vibration.] A. Koenig. ' Bemerkungen iiber angeborene totale Farbenblindheit.' [Shows how Uhthoff's results confirm the author's theory as regards the central scotoma, nystagmus, quantitative determinations on spectral comple- mentaries, and comparative visual acuity of normal and totally colour- blind eyes.] Literaturbericht. Vol. xxi., Heft 1 und 2. H. Gv Hamaker. ' Ueber Nachbilder nach momentaner Helligkeit.' [Experi- ments with resting stimulus (method of Hess and Bosscha), and with moving stimulus (method of Bidwell). Hypothesis of distribution of
