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groups appear highly specialized and in their permanent form from 

 the first. So-called intermediate forms like Cheirostrobus appear long 

 after the forms they are supposed to connect. Genera and species that 

 vary now have always varied and the limits of variation now and in 

 the past have been the same and definitely prescribed. In short Zeil- 

 lar believes that the evolution of all groups is a matter almost purely 

 of speculation. Doubtless most scientists will fail to accept Zeiller's 

 views as to evolution, and yet it may be well to put a brake now and 

 then to unlimited speculation ; a perusal of Zeiller's final chapter cer- 

 tainly compels one to do that. — H. C. Cowles. 



A Topographic Study of the Islands of Southern California. By 

 W. S.Tangier Smith. Bulletin of the Departmentof Geology. 

 University of California, Vol. II, pp. 179-230. 1900. 



This bulletin involves an account of certain islands which have 

 been studied in the field, and of others which have been studied from 

 maps only. Following a description of the general topography of the 

 islands, there is a somewhat full discussion of certain coastal features, 

 especially of wave-cut terraces, and of wave and current-built features. 

 This discussion is incisive, and will be of service to the student of 

 coastal topography. 



Following the descriptive matter there is a sketch of the history of 

 the islands, from which the following extracts are made : 



It is generally assumed that the broad physical features of the Pacific 

 Coast were largely developed during the prolonged period of erosion between 

 the Miocene and Pliocene, 1 and that these forms have been modified more or 

 less by subsequent movements, both general and local, as well as by subse- 

 quent erosion and deposition. During the Miocene the land was depressed, 

 as indicated by the Miocene deposits, the nonconformity between these and 

 the Pliocene deposits showing a period of subaerial erosion, during which the 

 land was more elevated than at present. This period of elevation and erosion 

 was followed by the Pliocene depression, during which deposits of great 

 thickness were laid down in favorable localities, the larger Miocene valleys 

 being filled to a greater or less extent with deposits which have since been 

 re-excavated to a greater or less extent. 



x By the long interval between the Miocene and Pliocene is doubtless meant the 

 long interval between the deposition of the California coastal Miocene, and the 

 Pliocene of the same region. 



