18 96.] Geology and Paleontology. 397 



Geology of the Nile Valley.— In a paper on the geology of the 

 Nile Valley, Prof. E. Hull calls attention to the two great periods of 

 erosion in this region, the first during the Miocene period, after the 

 elevation of the Libyan region at the close of Eocene times, and the 

 second during a " pluvial " period extending from late Pliocene times 

 into and including the Plistocene. In the second part of the paper 

 the terraces of the Nile Valley are described and full details given of 

 the characters of a second terrace, at a height varying from 50 to 100 

 feet above the lower one, which is flooded at the present day. This 

 second terrace is traceable at intervals for a distance of between 600 

 and 700 miles above Cairo. Two old river channels are also described, 

 one at Kom Ombo and the other at Assuan itself. The author dis- 

 cusses the mode of origin of the second terrace and the old river val- 

 leys, and believes them to be due to the former greater volume of the 

 river and not to the subsequent erosion of the valley. He gives fur- 

 ther evidence of the existence of meteorological conditions sufficient to 

 give rise to a " plnvial " period, and points out that other authors have 

 also considered that the volume of the Nile was greater in former 

 times. (Nature, March, 1896.) 



The Antarctic Continent. — Mr. C. Hedley has published the 

 data to date concerning the forms of life held as common stock by the 

 converging land masses of the southern continent, together with the 

 conclusions reached by several naturalists as to a former anr 

 area and the continuity of the southern land masses. The author 

 states that the evidence collected tends to show Antarctica as an un- 

 stable area, at one time dissolving into an archipelago, at another re- 

 solving itself into a continent. From the distribution of the pond 

 Bnail < Tundhichia, he argues a narrow land connection during Mesozoic 

 time between Tasmania and Terra del Fuego across the south pole, 

 and that New Zealand at that time reached sufficiently near to this 

 Antarctic land to receive by flight or drift many plants and animals 

 (Proceeds. Koy. Soc. N. S. Wales, 1895). 



Two Epochs in Vegetable Paleontology.— A late number of 

 Science contains a tribute by Lester Ward to the memory of two emi- 

 nent paleontologists, Marquis de Saporta and Professor William C. 

 In the author's judgment, the most important contribu- 

 tion of the former to science is the conclusion that the most important 

 subdivisions of the geological scale must be drawn at different points 

 for plant development from those at which they are commonly drawn 

 for animal development. For example, the Mesophytic age properly 



