Reviews — Dr. CrolVs Life and Work. ' ^ 



Interrupted rows of tubercles appear ia certain places along these 

 lines of growth. 



Size. — The largest dorsal observed was 19 mm. long and 20 mm. 

 wide. A ventral valve of corresponding size would be 1mm. longer. 

 Height of each valve about 5 mm. 



Horizon and Locality. — In the olive-grey sandstones of Division \h 

 of the St. John Group at Long Island in Kennebecasis Bay, King's 

 County, N. B. Canada. The exact horizon in Band h is uncertain : 

 there are about fifty feet in thickness of these sandstones exposed, 

 and they have the aspect of Assises 2 to 4 ; being from the upper 

 part of the sandstones the species is probably from Assise 3 or 

 Assise 4. These shells are found sparsely distributed in sporadic, 

 lenticular layers, having the valves promiscuously packed within 

 each other, as though after death they had been somewhat rolled 

 on a beach, or in a shallow sea. 



Further particulars of this species will be given in an article 

 in preparation for the Royal Society of Canada. 



St. John, N. B. Canada. 



S, IE ^^ I IE "V^ S. 



I. — Dr. Croll's Life and Work. By James Campbell Irons, 

 M.A. pp. 553, including Index and two Portraits. (E. 

 Stanford, 1896. Price 12s.) 



SIX years have elapsed since the death of Dr. Croll, and we are 

 now presented with a Memoir of his Life and Work from the 

 pen of his Edinburgh friend, Mr. J. C. Irons, assisted in some 

 degree by his brother, the Rev. David E. Irons, of Glasgow. We 

 quite agree with the author that the life of such a man, "recording 

 the triumph over his early struggles, his scientific researches, which 

 secured him a worldwide reputation as an original thinker, and 

 Lis earnest belief in the Christian faith," should prove interesting. 

 There is something fascinating in Croll's biography. His was an 

 euiinently Scottish type of character, and it may be safely asserted 

 tliat no other country than North Britain could have produced suck 

 a marked individuality. 



His autobiographical sketch (pp. 9-41), constituting a sort of 

 introduction to the present volume, should be read carefully in 

 order to understand the man. We thus realize, from the perusal 

 of a few clearly-written pages, his struggles with poverty and 

 ill-health, his thirst for knowledge, his natural inclination towards 

 metaphysics, his ultimate absorption in physical speculations, his 

 fortunate appointment as doorkeeper at the Andersonian Museum 

 in Glasgow, and, lastly, his acceptance of employment on the Geo- 

 logical Survey of Scotland. It is only right to add that he tells 

 us of his general indifference, in the outset of his career, for sciences 

 involving so much detail as geology and chemistry. As regards the 

 former, he observes (p. 14) that it is the only science on which (with 



