Reviews and Notices of BooJcs, 465 



ducting their researches during the dawning of the science, if not 

 also in setting at rest some of the questions upon which different 

 opinions have arisen. Its execution is the production of Mr. Geikie, 

 at the request of and aided by Sir Roderick Murchison, who 

 felt, he says, " aware that in addition to all that had been done in 

 the north, Mr. Geikie's intimate acquaintance with the rocks of 

 the south would render the work of essential service in advancing 

 Scottish geology." There is prefixed to the map an explanatory 

 sketch by Sir Roderick of its various sections, which throws much 

 interesting light upon the progress of discovery ; and the topo- 

 graphy has been laid down by Mr. A. Keith Johnston, who, as a 

 geographer, has long enjoyed a world-wide reputation. Sir 

 Roderick himself, with the assistance of his colleagues, has com- 

 pleted the map by adding to it many names of places of geolo- 

 gical importance. The combined labours of men so distinguished 

 in their respective walks as those to whom we owe the construc- 

 tion of this map, could not fail to prove eminently successful ; and 

 we have in it, accordingly, one of the best manuals for the study 

 of the geology of our native country that has yet come under 

 our notice. 



Prof. Hall on ReceptacuUtes. 



Prof. Hall sends to us a sheet of his forthcoming report on 

 Wisconsin, containing among other matters, notices of several 

 species of the remarkable genus Receptaculites, found principally 

 in the lead-bearing limestones of that State. Two of these had 

 been previously discovered and described by Dr. D. D. Owen, 

 under the generic names Coscinopora and Gelenoides. Prof. Hall 

 refers both, and four other species found with them, to the genus 

 Receptaculites, and after noticing the new facts in the structure 

 of these fossils stated by Salter in the 1st decade of organic re- 

 mains, issued by the Canadian Geological Survey, gives the fol- 

 lowing amended description of the genus. 



Generic Characters. — Body consisting of an infundibuliform 

 spreading disc, more or less concave at the centre, depressed- 

 orbicular, and globose. The spreading discoid forms consist of 

 a range of vertical cells in single series ; the orbicular discoid 

 forms have radiated curving cells which are directed from the 

 centre or axis towards the margin, their length and curvature 

 depending on the size and form of the mass ; the foramnia or cells 



Can. Nat. 4 . Vol. VI. No. 6. 



