292 founial of Comparative Neurology and Psychology. 



crease in temperature, as at night-fall, independent of any decrease in 

 light, causes the insets to settle down ; and it is probably the daily 

 changes of temperature which make V. antiopa retreat into hiding- 

 places at night and emerge in the morning. 



It is not true, as has been paradoxically alleged, "that moths, 

 which avoid daylight, fly into a flame at night, while butterflies, which 

 fly by day, do not possess this fatal instinct." Butterflies also fly into 

 a flame. The author does not confirm the hypotheses put forward by 

 LoEB and by Davenport in order to explain this supposed paradox. 



E. B. H. 



Hyde, Ida H. The Nerve Distribution in the Eye of Pecten Irradians. Art. 

 XXIV, pp. 473-482, pi. 34. 



The application of improved methods in histological research to 

 the eye of Fecie?i indicates, according to the findings of Dr. Hyde, 

 that the descriptions of this organ given by Patten, Hensen and oth- 

 ers are not entirely reliable. 



A brief but clear description of the histology of the organ is given, 

 and the author then turns to a more detailed consideration of the nerve 

 supply and of the retinal elements. The main conclusions of the paper 

 are thus stated: i. The rods are not, as was formerly supposed, 

 innervated by fibers from at least three series of nerves. "2. The so- 

 called retinophorae are not the visual sensory cells ^^:hose peripheral 

 fibers form the basal optic nerve, but they are the su})porting cells of 

 the median layer of the retina. 3. The inner ganglionic cells do not 

 connect with the side branch of the optic nerve, but are the nerve- 

 cells of the bipolar nerve elements. 4. The outer ganglionic cells form 

 a single layer whose inner fibers are disp(jsed in a special reticular 

 structure in the retina and whose outer fibers make direct connection 

 with the side branch of the optic nerve." 



The author believes that the visual apparatus of the retina is com- 

 posed of afferent and efferent neurones, and that the rods are true 

 peripheral visual neurones. 



The text is accompanied by an excellent plate which gives the 

 general histology of the eye in one figure, and in others the details of 

 structure of the retinal' elements, together-with their ganglionic con- 

 nections. R. M. V. 



