37° The Upper Elf Loch, Braids. [Sess. 



October last to the beginning of February in the present year, 

 was abnormally mild. According to Mr E. C. Mossman, on 

 the 16th of October 1897 one of the most noteworthy bursts 

 of autumnal warmth ever recorded in Edinburgh set in. Mild 

 weather continued to prevail throughout November; and 

 although there was a cold " snap " in December, high tem- 

 peratures again prevailed, continuing throughout January — 

 the mean temperature of that month being 44°"6, or 7° - 8 in 

 excess of the average January temperature deduced from the 

 records of the last 134 years. That the filling up of a con- 

 siderable portion of the loch by aquatic vegetation was, to a 

 large extent, due to these favourable weather conditions, there 

 can be little doubt. Whether it may ever again assume its 

 former dimensions is very doubtful ; indeed, the silting-up 

 process is more likely to go on apace. A very interesting 

 view of the loch, from a photograph taken by Dr Davies in 

 the spring of this year (1898), is here given, showing the 

 growth of vegetation at the north-west part. 



We looked forward with considerable interest to the effect 

 of the past mild season on the inhabitants of the loch with 

 the advent of spring ; but by the beginning of February frost 

 had set in, and at our visit on the 5th of that month the 

 tarn was covered with a thick coating of ice, which had to be 

 broken in order to permit of a gathering being made. Life, 

 however, even under these adverse conditions, was found to 

 be abundant. Hundreds of caddis-worms were busy con- 

 structing their tiny dwellings ; beetles and curious-looking 

 larval forms were largely in evidence ; entomostraca were 

 particularly lively and numerous ; while desmids and diatoms, 

 with a few of the motile algae, were observed. That all had 

 been stirred into unwonted animation by the mildness of the 

 winter was very evident. 



Before leaving this February gathering, some interesting 

 " finds " then made may be briefly referred to. The first was 

 a Water Boatman (Notonecta glauca), which had attached to 

 the hinder part of its body a large number of young ostracods 

 (Cyclocypris serena). The problem remains whether these 

 ostracods were parasitic at this stage, or whether they had 

 become attached to the beetle accidentally. We are not 

 aware of such a case having been recorded. Another curious 



