88 NOTES AND COMMENTS [august 



relations of the former to the stalk, the author states that the evidence 

 in favour of the originally paired character of the parietal eye is 

 derived principally from the fact that it arises to the left of the median 

 line, while the stalk is practically median, and therefore slightly to the 

 right of the eye. Accordingly the parietal eye in Sphenodon is 

 regarded as the left of the original pair, while the right one is repre- 

 sented by the parietal stalk. It is shown that the origin of the latter 

 appears to be precisely similar to that of the former ; and the two 

 have also a very similar structure, although the stalk never acquires 

 the same degree of perfection as the eye. 



The relations between the parietal stalk, the " epiphysis," and the 

 brain are next discussed, not only in Sphenodon, but in Lizards, Cyclo- 

 stomes, and Fishes. It is shown that in the two reptilian groups the 

 epiphysis, or pineal gland, is a composite structure, in which the para- 

 physis takes a large share, whereas the parts comparable to the 

 epiphysial outgrowths of Fishes form but a small one. In Lizards 

 the stalk may represent either the right or the left parietal eye- 

 Beyond that of fellowship, the parietal eye has no real connection with 

 the parietal stalk, being supplied with a special nerve of its own quite 

 distinct from the stalk. Finally, it is inferred that the ancestors of 

 existing Vertebrates were furnished with a pair of parietal eyes, which 

 may have been serially homologous with the existing functional pair of 

 ordinary eyes. 



The Expansion of the Empire of Hibbed Toads. 



A single ribbed toad has been found at Humptulips, Washington, 

 U.S.A. This simple statement involves a noteworthy fact. The sub- 

 order of tailless batrachians, known as Costata, embracing the single 

 family Discoglossidae, to which the new genus belongs, " has been 

 credited with a most extraordinary geographic distribution. Until 

 now it was composed of four genera, three of which are confined to 

 the south-western corner of the palaearctic region, except a single species 

 at the south-eastern end of the same region. The fourth genus, com- 

 posed of a single species, represents, alone, the batrachia in New 

 Zealand. None of the seven species known to form this sub-order 

 consequently had been found in the Western Hemisphere at all, and 

 none has thus far been taken in tropical Africa, Australia, or Asia, 

 with the above exception. The addition of a typical costate genus to 

 the fauna of North America is therefore not only an interesting- 

 novelty in itself, but it emphasises the fact that we have as yet much 

 to learn about the geographical distribution of the vertebrates even in 

 regions which have been fairly well explored." Thus writes Mr. 

 Leonhard Stejneger, who describes the specimen in Proceedings of the 

 U. S. National Museum (xxi. pp. 899-901, pi. lxxxix. June 1899). 



