560 



Prof. 0. Heer. On the 



[June 17, 



tion in other media ; and, lastly, whether by any means the Bacillus 

 might again acquire the power of producing the disease — these are 

 questions which can only be determined by further experiment. 



X. "On the Miocene Plants discovered on the Mackenzie 

 River." By Professor Oswald Heer, of Zurich. Commu- 

 nicated by Robert H. Scott, F.R.S. Received June 16, 

 1880. 



On his return from his "searching expedition" to Arctic America 

 of the year 1848, Sir John Richardson brought to London a box of 

 fossil plant-remains, which he had collected on the Mackenzie River, 

 between Fort Norman and the Great Bear Lake River, in latitude 

 65° N. 



The deposits from whence the specimens were obtained had been 

 discovered by Sir Alexander Mackenzie, in 1785, and visited by Sir J. 

 Franklin and Sir John (then Dr.) Richardson in 1825 ; but it was not 

 until his second visit that Richardson was able to bring away speci- 

 mens (Journal, vol. i, p. 186). 



This first collection contained seventeen specimens, of which only 

 fourteen allowed of exact determination, but it presented features of 

 great interest, as it gave us the first indications of the character of 

 the Miocene Flora of these inaccessible regions of North America. 



The importance of procuring more copious materials for the study 

 of these deposits hardly requires to be stated, and, accordingly, in the 

 year 1871, Mr. Robert H. Scott, F.R.S. , and Dr. John Rae, F.R.S. 

 (who had himself accompanied Sir John Richardson on his expedition 

 in 1848, when the first specimens were collected), obtained from the 

 Government Grant Committee the sum of £50 to defray the cost of 

 procuring and forwarding to London a collection of these plant- 

 remains. The actual expenses incurred have, however, fallen far 

 short of the amount received. 



The kind offices of Mr. W. Hardisty, Chief Factor of the Hudson's 

 Bay Company's Service, were enlisted for the task, which was not an 

 easy one to carry out. The locality is distant from any inhabited 

 port, and is merely passed by the boats on their annual trading 

 journeys up and- down the river, when the men are fully employed in 

 making the best use they can of the short period available for naviga- 

 tion, and have but little time to look for fossils. 



More than one attempt was made to send boxes to London ; but as 

 this involved a long journey by boat before they reached the port of 

 shipment, it is not to be wondered at that two or three cases failed to 

 reach their destination. At last, in the summer of 1879, Dr. Rae 

 learnt that a box of fossils, addressed to him, was lying at Manitoba 



