EDITORIAL 77 



Tomieria, appears to have been about 150 feet long, almost 

 twice the length of Diplodocus carnegii, and so enormous are 

 its proportions that one is driven to the conclusion that it 

 could have been no dweller on the land that only the waters 

 of the sea could have supported the monster's " weary 

 length." * 



An important contribution to our knowledge of Scottish 

 Spiders is published by Dr A. Randell Jackson. 2 This 

 article contains full details of species collected during the 

 summer of 1913 in the following localities: Aberlady, The 

 Trossachs, Rannoch, Schiehallion, Ben Nevis, Mallaig, and 

 Crinan. Thirteen species are added to the Scottish list, 

 and of these eight are new to Britain and two new to 

 science. The two plates which accompany the paper contain 

 carefully executed drawings of the details useful for purposes 

 of identification, and several species are dealt with in these 

 figures. The new species are designated Leptyphantes 

 cacuminum and Robertus scoticus. 



We learn from Nature* that an account of some interest- 

 ing experiments conducted by Dr von Fritsch and Herr 

 Rupelvvieser on the perception of colour by the Water-Flea 

 (JDapJinia) has been recently published in the Biologisches 

 Centralblatt. By means of a powerful Osram electric lamp 

 and fluid light-filters or coloured glass screens, it was ascer- 

 tained that these little crustaceans remain evenly distributed 

 under a medium intensity of white light, but when the 

 intensity is increased they move away from the source of the 

 light, and vice versa. They are attracted by red, yellow, and 

 green rays, but repelled by blue-green, blue, and violet ; 

 hence the authors have come to the conclusion that Daphnia 

 has a distinct colour-sense in addition to the perception of 

 varying degrees of light intensity. 



1 Field, 14th March, p. 534. 



2 " A Contribution to the Spider Fauna of Scotland," Proc. Royal 

 Physical Society, vol. xix., No. 5, pp. 108-128, pis. ii. and iii. (February 



1914). 



3 26th February 1914, p. 726. 



