o<32 ANNUAL OF SCIENTIFIC DISCOVERY. 



those ancient forests which once covered so large a portion of Ireland still 

 exist on the Earl of Arran's property at the present time. After the plants 

 which form this variety of bog were enumerated, the kind called mountain 

 bog was next considered, which sometimes accumulates to a great depth on 

 the tops of mountains, at elevations varying from one thousand to two 

 thousand feet. The Sphagnums do not enter so largely into the composition 

 of this kind, but their place is supplied by the gray moss, Racomitriinn 

 lamiginosum. The conclusions Mr. Moore has come to on this subject are 

 the following, namely, that so far as proofs exist, the same plants which are 

 now forming the bogs of Ireland have done so from the bottom upwards, 

 though probably at different ratios, as drainage has increased, and that all 

 the species are still in existence in Ireland which have ever formed any part 

 of them. These formations he considers to be of a more recent date than 

 the glacial epochs of geologists, with probably a single exception. 



NEW VEGETABLE GUM. 



A committee of the Society of Arts in London has recently reported on 

 the new gum pauchonte, the product of a tree similar to that which produces 

 gutta-percha. This gum is hard and friable at ordinary temperatures, but 

 by the application of heat it becomes pasty and viscous, and when once it is 

 in this state it does not return to its original condition. When boiled in 

 water, it assumes a reddish-broAvn color, and makes the water a little soapy. 

 Many reagents act upon it precisely as they do upon gutta-percha. The 

 new gum cannot take the place of gutta-percha, but from twenty to thirty 

 per cent, of it can be mixed with gutta-percha without sensibly changing its 

 properties. 



ON THE INFLUENCE OF EXTREME COLD ON SEEDS. 



Some experiments, more thorough and satisfactory than those of Edwards 

 and Colin, have been made during the present year by Prof. Elie Wartmann, 

 of Geneva, on the influence of extreme cold upon the seeds of plants. Nine 

 varieties of seeds, some of them tropical, were selected. They were placed 

 in hermetically sealed tubes, and submitted to a cold as severe as science 

 can produce. Some remained fifteen days in a mixture of snow and salt; 

 some were plunged into a bath of snow and sulphuric acid. On the fifth 

 of April, they were all sown in pots placed in the open air. They all germi- 

 nated, and those which had undergone the rigors of frigidity produced 

 plants as robust as those which had not been submitted to this test. 



