276 Reviews — Waagen's Falceo geography of India. 



undescribed, 1 though the most extensive memoir on the local geology 

 by the Indian Survey (that on the Salt Eange) has been for years 

 awaiting publication, and has lain printed but unissued since the 

 summer of 1877. 



Dr. Waagen's Palaeozoic continental shore-line edges the Salt 

 Eange escarpment, in which there occurs a group of beds said to 

 have been prematurely referred to the Silurian age, 2 as well as a 

 later development of generally-admitted (though the author uses the 

 term 'so-called') Carboniferous strata. These marine groups are cut 

 off by the escarpment on the south side of the range ; the upper one 

 reappears strongly on the Indus to the west, and it is evident the 

 beds once extended further to the southward, hence there is absolutely 

 no reason why they might not have reached as far as Delhi, or be 

 even now buried beneath the great Sind-Punjab deserts. Here, at 

 least, the author's conclusion as to continental limits must be founded 

 on loose conjecture rather than on fact. 



But in still earlier Palaeozoic times an adjacent southern continent 

 is better indicated amongst the older Salt Eange strata, by the occur- 

 rence of derived crystalline boulders in an earthy matrix, of kinds 

 unknown in the crystalline series to the north. The deposits are 

 unfossiliferous, and their partly shore-like aspect or association with 

 enormous layers of salt and gypsum are but slight reasons for 

 asserting their roai'ine, estuarine, or terrestrial origin. Consequently 

 the presumed continental boundary in this direction at that early age 

 becomes hazy if not totally obscure. 



The supposed Palaeozoic Attock slates, which occur further to the 

 north, and comprise many sandstones and limestones as well, may 

 be of course marine, though, in the absence of fossils, both this 

 point and their exact age are quite incapable of proof; they are, 

 nevertheless, included in Dr. Waagen's Palaeozoic "slaty facies." 



Nor can we find more satisfactory reason why the author supposes 

 the outer Crystalline zone of the Himalayas to have formed the 

 coast-range of a continent for most of the Mesozoic period ; the only 

 one he advances seems to be merely the absence of as yet recorded 

 marine beds of this age along the south flanks of these mountains. 

 The Himalayan crystalline rocks, however, are not the same as those 

 of peninsular India, and he admits the possibility of their represent- 

 ing Palaeozoic beds in a metamorphosed state. It is plain that a 

 series of rocks, thus altered beyond recognition, might be of any age 

 anterior to the Tertiary elevation of the range, and equally plain 

 how slender and transparent is the assumption upon which the 

 imaginary coast-line of a great ancient continent has been drawn. 



Again, the author points out that his Triassic continental boundary 

 line is visible in the Salt Eange, but omits to say that the formation 



1 See papers by Fleming, Asiat. Soc. Bengal. Also Quart. Journ. Geol. Soc. 

 London, 1874-78. Eecords Geol. Surv. Ind. vols, iii. vi. vii. viii. Memoirs Geol. 

 Surv. Ind. vol. xi. and xiv. (" to be issued shortly.") 



2 Dr. "Waagen himself, when in India, favoured this view, and never suggested its 

 being doubtful, though the evidence was in his hands, in the shape of shells of an 

 Obolns, determined as Silurian by the late Dr. Stoliczka. 



