Reviews — Petrology for Students. 43 



BracMopod faunas of these districts and the fossil faunas found in 

 the Upper Tertiary of the neighbouring lands. Thus the recent 

 New Zealand fauna is a diminished representative of the Oamaruian 

 fauna ; the recent Australian fauna (excepting the subtropical part 

 on the north-east coast) is a remnant of the Australian Miocene 

 fauna of that continent. The Antarctic recent fauna is least like the 

 Tertiary fauna of that district, owing to the j)resence of recent 

 northern immigrants [Macandrevia, Frieleia, Magellania s.str.). 

 The author concludes that the distribution of the recent brachiopods 

 in the Southern Seas is explained by the ancestral distribution in 

 the Miocene period, and that it calls for no shallow- water connexions 

 between the various southern continents and islands since that 

 date, except j)erha23s between South America and the Antarctic. 



On the other hand, the resemblances between the Oligocene-Miocene 

 faunas of the four regions named indicate the existence at an earlier 

 date of greater means of communication between the lands 

 bordering the Southern Pacific Ocean than exists at the present day . 



The genera Argyrotheca, Amphithyris, Kraussina, and Megerlina 

 are found in the New Zealand and Australian districts, but not 

 in the Antarctic and South American ; as these genera occur also 

 in the Indian Ocean and the Mediterranean the author suggests 

 that Australia had former connexions with South Africa and the 

 Mediterranean. Dr. Thomson states that the moUuscan faunas of 

 the Patagonian of South America and the Oamaruian of New Zealand 

 give evidence of a much warmer climate than is found at present 

 in these regions. The occurrence of some species and genera of 

 Brachiopods in the Oligocene-Miocene of the Antarctic which are also 

 found in the Patagonian, the Oamaruian, and the " Miocene " of 

 Australia suggests a warmer climate for the Antarctic seas of that 

 period. 



The author urges the desirability of further dredging on the 

 submarine banks of the Southern and Pacific Oceans ; if these 

 banks are due to the sinking of land masses the remains of coastal 

 faunas should be found on them. The concluding pages of the work 

 give a brief account of the diastrophic history of New Zealand. 

 The map of the Antarctic and Southern Oceans shows the 1,000 

 and 2,000 fathom contours. 



Petrology for Students. By Alfred Harker, M.A., LL.D., 

 F.R.S., F.O.S. 5th edition, revised, pp. 300, with 100 figures. 

 Cambridge University Press, 1919. Price 8s. 6cl. net. 

 R. HARKER has been enabled during the comparative freedom 

 from the burden of teaching afforded by the War to prepare 

 a fifth and further revised edition of his standard textbook oi 

 petrology, which is too well known to require a detailed notice 

 here. Considerable parts of the work have been rewritten, and the 

 results of all important recent work is incorporated. The author 



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