1898.] Stubbs and Adams. — Molhisca of South-west Ireland. 263 



of which, however, were more than half grown, and many were quite 

 babies. The smallest (li mm. in altitude) was especially interesting, as 

 it showed the young shell to be of the same form as pej-egra 

 and not intorted (see figure). When placed in a glass of 

 water some crawled up the side out of water for about an 

 inch, but soon descended. Their crawling movement is 

 rapid, and the figure drawn by Mr. J. W. Taylor in Part I. 

 of his " Monograph " admirably shows the attitude. Our 

 independent estimate of the size of Lake Crincaum corresponded with 

 that of Messrs. Collier and Chaster. 



The shell apparently keeps on breeding for a long period, as we found 

 masses of spawn in a very early stage attached to stones. 



Llmnaea pcrcgra, IMliller. — Near Aghadoe in a small stream we 

 took a good series of thin medium-sized shells with a tendency to 

 scalariformity, among which we found after cleaning three of the rare 

 var. Candida, perfectly white. 



Aplexa hypnorum, L. — This is also a specific addition to Mr. 

 Standen's list. It occurred with Planoibis spirorbis in a small trickling 

 ditch near Aghadoe. 



Northampton. 



GEOI.OGY FOR BEGINNERS. 



Geoloery for Begrinners. By W. W. Watts, M.A., F.G.S. With 

 310 illustrations. London: Macmillan & Co., 1898. Price 25-. 6<f. 



The author of this excellent little work will not feel it as any disparage, 

 ment when we saj^ that its most original feature lies in the illustrations- 

 For very many of these, notably those of microscopic sections, are his 

 own work; while others have been gathered, with conspicuous judg- 

 ment, from the geological series formed by friends throughout the 

 British Isles. The clear little blocks of fossils are mostly from Zittel's 

 latest manual on Palaeontology. 



We could have wished that more of the landscapes could have been 

 produced on the scale of Mr. Achison's beautiful " Gwm glas," or Mr. 

 Welch's brilliant " Overfold " on p. 107. But that would have made an 

 expensive feature in a work that aims at carrying geology into schools ; 

 and we are thus left to hope that the teachers themselves will make 

 collections of photographs on a larger scale, illustrating the phenomena 

 so clearly outlined in the book. With its simple and lucid style, and 

 its admirable typograph3% the work appeals at once to the young reader. 



Prof. Watts assumes that his readers have no preliminary chemical 

 knowledge — which is likely to be true in many cases. But, in view of 

 the struggle that science still has to make in educational circles, is it 

 not better to boldly presume some knowledge, and to sketch in the 

 necessary facts as a reminder, rather than as part of a lesson in pure 



