IQ2 Joiir?ial of Cojnparative Neurology and Psychology. 



sea-water form a large single median eye. This condition is comparable to the 

 one eyed human monsters known as Cyclops, Cyclopia or Synophthalmia. 



The single eye results from an antero-medio-ventral fusion of the elements of 

 the two optic vesicles at an early developmental stage. This fusion is more or 

 less complete in the different embryos. 



The large compound optic cup induces the formation of a single lens. This 

 lens is formed from ectoderm different in position from that of the normal lens 

 forming region. The lens is abnormally large in size as is also the optic cup, and 

 the size of the former varies directly with that of the latter. It is probable that 

 there is no localization of lens forming substance in the ectoderm of the fish embryo. 

 This inter-relationship in the development of the optic cup and lens is interestingly 

 compared with the processes of development in the amphibian eye as shown by 

 recent experiments. 



Mixed sea-water solutions of MgCl2 and NaCl also cause the one eyed condition. 

 Since such a defect is characteristic of the MgCl, action when used in sea-water 

 solutions one must infer that the Mg constituent in the mixture is responsible for 

 the result. 



On the Place of Origin and Method of Distribution of Taste Buds in Ameiurus 

 melas. By F. L. Landacre, Ohio State University. 

 This paper appeared in full in the last issue of this Journal. 



The Central Reflex Connections of Cutaneous Taste Buds in the Codfish and the 

 Catfish: An Illustration of Functional Adaptation in the Nervous System. 

 By C. JuDSON Herrick, Denison University. 

 The substance ot this paper appeared in the article by the same author in the 



last issue of this Journal. 



Some Little-known Shark Brains, with Suggestions as to Methods. By Burt G. 



Wilder, Cornell University. 



This paper continues that of which an abstract was printed in Science for May 

 26, 1905. Now first, so far as I know, are shown the brains of Heterodontus (Ces- 

 tracion) and Pristiophorus. With the former the cerebrum and cerebellum resem- 

 ble those of the "acanth" (Squalus acanthias), indicating an antiquity little if any 

 greater. Notwithstanding certain ectal resemblances of the two dentirostral genera, 

 Pristis, the "saw-ray" and Pristiophorus, the "saw-shark," their brains differ 

 markedly, the latter being the more primitive. Their inclusion within the same 

 family or even the same division would seem to me an error only less in degree than 

 would be their combination with Xiphias, Polyodon and Psephurus as "Rostrata," 

 or than was Gunther's association of Ganoids and Selachians as " Palaeichthyes," 

 aptly characterized by Gill as a "piece of scientific gaucherie." Upon encephalic 

 grounds I think Pristiophorus and Scymnorhinus should be excluded from the 

 Squalidae, and Sphyrna from the Carchariidas. The brain of each selachian 

 genus is, I think, recognizable, but I am less certain as to family forms. The 

 Notidanoid or Diplospondylous type is well marked, and includes Scymnorhinus. 

 At present the rays cannot be distinguished from the sharks in any such simple 

 way as, e. g., the Anura may be from the Urodela by the secondary fusion of the 

 olfactory bulbs. Perhaps, in no shark is the prosocele so nearly obliterated as 



