520 Notices of Memoirs—Prof. E. mill— Fishes in Sea of Galilee. 



elevation by jerks, therefore, be postulated or not, all liope of corre- 

 lating these terraces throughout the country must be deferred until 

 their heights have been accurately determined by level. The measure- 

 ments hitherto made, not even excepting those of Professors Kjerulf 

 and Mohn, are probably inadequate for the purpose. This observation 

 seems to apply also to the terraces graven in rock. In their aneroid 

 measurements of the upper strand-line at Trondhjem these observers 

 differ by fifty -five feet. 4. On entering the mouth of the Trondhjem 

 Valley, the terraces come under an influence other than that of the 

 sea-waves. The valley was worked out, in deposits partly levelled 

 out by the sea, according to the laws of river terracing under the 

 accelerating influences of a falling sea-level. The processes of 

 automatic river terracing are beautifully exemplified within the 

 district mapped, in the deep lobe-shaped curve of the river just 

 before it enters the sea. The terraces have been added one after 

 another to .the point of the lobe of land thus surrounded, which is 

 known as Oen. 



IV. — Some Eesults of the Crystallographic Study of Danburite. 

 By Dr. Max Schuster. 



IN studying the characters of the faces and the structure of the 

 Danburite crystals found in Switzerland, the author has met with 

 vicinal faces of a peculiar kind, for which he proposes the term 

 'transitional faces' (Tschermak, Min. Mittheil. vi. 1884, p. 511). 

 Attention is called to the fact that these faces are easily affected by 

 those causes which produce an unequal development of faces other- 

 wise symmetrically disposed, and an illustration is given of the way 

 in which their indices are numerically related to those of the principal 

 faces of the crystal. 



Paper read in Section D (Biology). 



V. — On the Origin of the Fishes of the Sea of Galilee. 



By Professor Edward Hull, LL.D., F.E.S., 



Director of the Geological Survey of Ireland. 



WHEN preparing a memoir for the Palestine Exploration Society 

 on the physical history of Arabia Petrgea and Palestine, I was 

 confronted with two biological problems : one on the origin of the 

 fauna of the Sea of Galilee (or Lake of Tiberias) ; the other on the 

 cause of the extreme dissimilarity between the faunas of the Eed Sea 

 and Mediterranean, notwithstanding the ascertained fact that the seas 

 themselves have been physically connected within very recent times. 

 With the former problem I propose here to deal as far as the fishes 

 are concerned ; with the latter I shall deal presently. 



The abundance of the fishes which inhabit the waters of the Sea 

 of Galilee is known both from sacred and secular history, and has 

 been testified to by several recent observers. The characters and 

 habits of these fishes have also been ably discussed and illustrated, 

 especially by Canon Tristram ^ and Professor L. Lartet,^ from which 

 it has been determined that nearly one-half of the species are 



^ Fauna and Flora of Palestine, preface, p. xii. Mem. Palestine Survey, 1884. 



2 Poissons et Eeptiles du Lac de Tiberiade, Archives du Musee d'Histoire 

 Naturelle deLyon, tomeiii. 1883. 



