122 The Irish Naturalist. June, 



A HANDY MAP. 



Stanford's Geological Map of Central Europe. London ; E. Stanford, 

 Dec. I., 191 1. Price 5s. 



This is a handy map for students, on the scale of i inch to 100 miles, 

 and is based on that issued by the International Geological Congress. 

 It extends from Gal way to Warsaw, and from Oporto to Corfu, and is 

 partly hand -coloured and partly colour -printed. The unfamiliar but 

 useful term Brioverian is applied to the pre -Cambrian rocks that cannot 

 be classified as schists. The grouping together of Upper Silurian and 

 Devonian strata seems unfortunate, especially for the areas where the 

 Old Red Sandstone type of the latter system prevails. The areas 

 covered by " Pleistocene and Recent " deposits are impressively revealed, 

 and we can even trace where the rivers streaming from the Pyrenees 

 have cut down through the glacial detritus to the Cainozoic beds below. 

 Since East Anglia is properly shown as covered by glacial drift, it might 

 have been well to apply the same scheme of colouring to the Irish plain, 

 as is indeed indicated on the map of the International Geological Congress. 

 The surprising youthfulness of Italy, where Cretaceous limestones are 

 just coming to light among the central gorges of the Apennines, and the 

 antiquity of the plateau of Bohemia, from which the Cretaceous film is 

 being swept away, are among the many features which are contrasted 

 on the map. For a general survey of European structure, its small scale 

 is a distinct advantage. 



^ G. A. J. C. 



BRITISH AND IRISH DESMIDIACEAE. 



A Monograph of the British Desmidiaceae. By W. West and G. S. 



West. Vol. iv. Pp. xvi. + 191, PI. 96 + 128. London ; Ray Society 

 1912. Price 25s., net. 



This work is continued along the same lines as the previous three volumes 

 published in 1904, 1905, and 1908, respectively. The present volume 

 completes the species of the genus Cosmarium, contains all the species of 

 the genera Xanthidium and Arthrodesmus and the first 41 species of the 

 genus Staurastrum, leaving 128 species of that genus for inclusion in the 

 next volume. Altogether 96 species are described in this volume, and of 

 these 64 species — exactly two -thirds — occur in Ireland. The following 

 three species occur in Ireland only ; — Cosmarium promontorium, W. & G. 

 West ; Xanthidium apiculiferum. West ; and Arthrodesmus trispinatiis, W. 

 and G. S. West. There are also several varieties confined to Ireland. 

 One species, Staurastrum disputatum W. & G. S. West, seems to be an 

 addition to the Irish flora. Five species are mentioned as occurring 

 on Clare Island. 



Only one misprint has been detected among the Irish localities, viz., 

 " Dcrrystrasna " on p. 84 which ought to be " Derrytrasna." As in 



