230 Reviews — Prof. Hull's Survey of Palestine. 



Palestine and Idumar this period is " one of disturbance and elevation, 

 of faulting and flexuring and denudation of strata." 



In the chapter on " Later Pliocene to Recent Beds (Pluvial)," the 

 author points out that after the leading features of the land and 

 coast-lines had been formed by denudation, there was a depression 

 of about 220 feet in relation to the present sea-level. The evidence 

 for this is the presence of raised beaches with recent shells in the 

 vicinity of Cairo, also near Gaza and Jaffa at elevations of about 220 

 feet. The author also discovered recent corals and shells in gravelly 

 beaches in the Arabah valley at elevations of 80 and 130 feet above 

 the sea-level. 



A depression of about 220 feet would unite the basins of the Eed 

 Sea with the Mediterranean, and at the shallowest part of the 

 channel between them there would be a depth of 150 to 170 feet of 

 water. On the theory of the union it is difficult to explain the 

 remarkable differentiation which exists between the faunas of the 

 Mediterranean and the Eed Sea at the present day, for if there was 

 such an open channel in Pliocene times, the period which has since 

 elapsed does not seem sufficiently long to have given rise to the 

 extreme dissimilarity which now exists. Prof. Hull assumes that 

 the two seas were disconnected in Miocene times and that the 

 differentiation which took place in that interval was not materially 

 interfered with by the Pliocene communication ; since the water was 

 not deep enough to allow of free commingling of the two faunas. 

 To most naturalists this will appear an unsatisfactory and untenable 

 explanation. 



The author refers in some detail to the terraces of marl silt and 

 gravel with fresh-water shells in the more elevated beds, which 

 mark the different elevations of the water in the Jordan-Arabah 

 valley up to a level of about 1400 feet above the present surface of 

 the Dead Sea, or about 100 feet above the Mediterranean. 



The Jordan-Arabah depression is ascribed to the direct result of a 

 fault or fissure of the crust, accompanied by a displacement of the 

 strata, arising from the tangential pressure of the Earth's crust due 

 to contraction, and the depression was produced at the close of the 

 Eocene period. It is thought probable that the first waters of the 

 Dead Sea basin were those remaining from the ocean itself, and that 

 the fauna of the Lake of Tiberias may thus have had, in the main, a 

 marine origin. The author does not venture to apply this theory to 

 the distinctive species of TJnio and other fresh-water mollusca, now 

 inhabiting the Jordan Valley, but regards the fishes as the descendants 

 of those which lived in the waters of the Eocene seas. It is, of 

 course, possible, but we should like to have seen some facts brought 

 forward in favour of the hypothesis. 



According to the author this isolated basin-full of Eocene salt- 

 water then suffered a process of contraction, whether from evapora- 

 tion or otherwise, is not stated, and at the close of the Miocene, or at 

 the commencement of the Pliocene, the waters had been reduced to 

 about the level they are at present, and in the meantime the region 

 was being carved out by denudation into the hills and valleys of the 

 present day. This contraction is correlated with a similar reduction 



