778 



land. A considerable propoilion of them re-appear in Shetland and 

 Orkney. The marine vegetation in these northern islands resembles 

 that of the north of Ireland, though there is a difference between them 

 of from four to five degrees of latitude. The marine plants of some 

 of the north-eastern counties of Scotland, intermediate in latitude, are 

 of more boreal character. The drifting of tropical fruits, &c., to the 

 western and northern parts of Ireland and Britain, is a proof of 

 the direction and presence of the Gulf-stream ; the development of 

 southern forms of Algae at the extreme northern parts is a proof of the 

 same, and, moreover, seems an indication of its influence in reference 

 to temperature. Are we to consider their absence from certain parts 

 of the east coast of North Britain as owing to a lower sea temperature 

 than in localities where they exist ? The portion of the coast in 

 question is precisely that which, from the generally understood course 

 of the Gulf-stream, may be least exposed to its influence. Investiga- 

 tions respecting the temperature of our seas are, however, still deside- 

 rata ; and, without such, an important modifying element has been 

 overlooked having reference to the climate of the British Islands. 



Prof. E. Forbes said that the distribution of marine animals corre- 

 sponded with that of marine plants. The same anomalies which 

 Dr. Dickie had pointed out with regard to plants existed with regard 

 to animals. Less attention had been given to the distribution of 

 marine Algae than to almost any other organic existences. With the 

 exception of the labours of Dr. Harvey, little or nothing has been 

 done. We wanted a more accurate knowledge of the temperature of 

 the ocean at different depths. [This hint resulted in a subsequent 

 recommendation from the Section, that the Government would prose- 

 cute this inquiry.] 



Prof Walker-Arnott said that he possessed waggon-loads of Algae 

 from all parts of the world, which were greatly at the service of any 

 botanist who would work at them. The collecting part of the task 

 had been done ; the naming and arranging were now alone necessary. 

 Dr. Harvey could do no more than he had done at present. 



Report on the Influence of the Solar Radiations on the Vital Powers 

 of Plants growing under different Atmospheric Conditions^ by Dr. 

 J. H. Gladstone. 



As a preliminary matter of inquiry, the mere effect of coloured 

 media in accelerating or retarding the growth of various kinds of plants 

 was tried. Hyacinths were chosen as the sample of bulbous-rooted 

 plants. Roots of as nearly as possible the same size and description 



