458 NATURAL SCIENCE. Dec. 



already alluded to, dealing with the correlation of the Gondwana 

 system. The other two summarise the evidence as to " The Age and 

 (Origin of the Himalayas," and give a sketch of the " Geological 

 History of the Indian Peninsula." Attention is paid to the recent 

 discussions upon the former, and the effort to prove that the Himalaya 

 are of only very late Tertiary age, and that they are even now under- 

 going elevation. It is, however, maintained that the old view that the 

 Himalaya are post-Eocene and pre-Pliocene is the correct one. The 

 contentions of Middlemiss that the mountains were partially formed 

 in pre-Tertiary times is also dismissed, but here the evidence is 

 apparently less conclusive ; the discussion of the subject leaves 

 one with the impression that perhaps Mesozoic movements in the area 

 were more important than has been believed. In discussing the 

 formation of the Himalaya, attention is called to the Rev. Osmond 

 Fisher's theory of mountain structure ; a modification in this is 

 proposed, and with this alteration the theory is said to find much 

 support and illustration in the facts of Himalayan geology. 



One of the most interesting points in which this edition differs 

 from its predecessor is the different conclusion arrived at in respect 

 to the formation of the Western Ghauts or Sahyadri Mountains. 

 These are unlike the hills on the eastern side of the peninsula, which 

 were grouped together in old geography books under the name of the 

 Eastern Ghauts. For the Sahyadri Mountains have long been known 

 to have a unity of structure, and to be of comparatively recent age. 

 The hills on the Madras side of the peninsula, on the other hand, are 

 not a single range, and were, with the Aravalli Mountains in 

 Rajputana, among the oldest geological features in the country. In 

 the 1879 edition the conclusion was maintained that the' western 

 scarps of the Sahyadri Mountains were formed by marine denudation, 

 and were carried back some distance into the Tertiary rocks. Mr. 

 Oldham, however, maintains that these mountains are the newest 

 feature in Indian geography, and that their abrupt western scarps. are 

 the direct result of a dislocation. His arguments, moreover, seem abso- 

 lutely conclusive as to the truth of this interesting and important view. 



A charming photo-gravure of the eastern spur of the famous peak 

 of Kanchanjanga (or Kichinjunga as it is probably better known in 

 England) forms a frontispiece to the volume. This is so good that 

 one wishes some more pliotographs of Indian scenery had been given 

 in the book. We should have been glad to have seen some of the 

 plates of fossils replaced by some of the photographs which have 

 adorned recent volumes of the Indian Survey Mcmoiys. In a general 

 book of this character, these would probably have been found of more 

 general use and interest than figures of fossils. 



Mr. Oldham is to be congratulated on the completion of his 

 laborious task of revision, and we hope when a third edition is required 

 the task will be placed in the hands of one who will do it with as 

 much knowledge and originality. 



J. W. G. 

 Amphioxus. 



Amphioxus and the Ancestry of the Vertebrates. By A. Willey, B.Sc. 

 Pp. xiv. and 316, with one plate and 135 illustrations, being Vol. II. of the 

 Columbia University Biological Series. New York and London : Macmillan 

 and Co. Price los. 6d. nett. 



The literature of Amphioxus is not so large as that of many other 

 groups ; but it is nevertheless of a decidedly respectable bulk, par- 

 ticularly if various papers which bear indirectly upon the problems 



