Literary Notices. xxiii 



that the dog is really conscious, in reality looks the other way. The 

 presence of consciousness for some time after birth would be a great 

 embarrassment to the economy of the animal. The relation between 

 consciousness and educability is not denied, but it does not follow that 

 the reflexes are not capable of education while the sphere of profitable 

 interference of the conscious is relatively very small. 



c. L. H. 



The Parapliysis.' 



This paper is mainly concerned with a summary of other and ear- 

 lier papers by the same author, with, however, some new observations 

 and an excellent series of photographs. He reiterates the belief that the 

 paraphysis is an evagination from the cerebrum and is only secondarily 

 associated with the diencephalon and that it represents, like the parie- 

 tal eye, an aborted sense organ. This seems to us an improbable view 

 and one requiring stronger evidence than that presented by the author's 

 photographs. Yet the remarkable constancy with which this structure 

 appears in the embryos of all vertebrates certainly does indicate that 

 the paraphysis has now or has had an important part to play in the evo- 

 lution of the vertebrate brain. Just what this part may be we cannot 

 by any means regard as satisfactorily determined. 



In an earher work the author described the parietal eye of Anguis 

 as originating by a constriction of the distal end of the pineal evagina- 

 tion essentially as described by Spencer and the majority of other in- 

 vestigators. Beraneck, however, finds that the parietal and pineal 

 evaginations have distinct origins from the roof of the diencephalon, 

 and now Francotte comes over to the same ground, the error in the 

 first case having arisen not from inaccuracy of observation, but from an 

 anomalous condition in the embryo under under investigation. Photo- 

 graphs of the normal and the abnormal brains are given. Five em- 

 bryos taken from the same mother were found all to present the same 

 anomaly. Whichever view of the origin of the parietal eye may 

 prove to be correct, this paper will do good service in calling attention 

 to a source of error and of disagreement in many another controversy 

 besides this one. It is a significant fact that it was during the same year 

 in which Francotte's paper appeared that Prenant published his paper 

 on accessory parietal eyes in Anguis fragilis, in which he made a sta- 



'Francotte, p. Notesur I'teil parietal I'epiphyse, la paraphyse et les plexus 

 choroides du trois^me ventricule. Bull. V Acad. Royak dt Belgique, 3 Series, 

 XXVII, 1894. 



