Proceedings of the British Association. 367 



Mr. Mackay read the Report which he had been last year request- 

 ed to prepare, " On the Geographical Distribution of the Plants of 

 Ireland." This contained a catalogue of one hundred and ninety five 

 of the more remarkable species, with a comparative view of such as 

 were common to the neighborhoods of Dublin, Edinburgh, and the 

 south coast of Scotland. And Mr. Mackay tlien entered into some 

 details illustrative of the more remarkable points of difference in the 

 vegetation of Ireland and Scotland. This difference might be partly 

 ascribed to the more southerly situation of Ireland, and the height 

 of its mountains being inferior to those of Scotland. Its greater ex- 

 posure to the influence of the western ocean gives it a inoister cli- 

 niate. Scotland is, in consequence, much the richer in alpine plants, 

 and Mr. Mackay enumerated fifty five species of the more remark- 

 able alpine and other plants natives of that country, which do not 

 occur in Ireland. Many plants on the western coast are natives of 

 the mountains of Spain and Portugal. A list was then given, in 

 which twenty one species were enumerated as natives of Ireland, 

 but which had not been found in any otlier parts of Great Britain, 

 and it was very remarkable that several of these were also to be 

 met with on the western side of the Pyrenees. In conclusion, Mr. 

 Mackay proposed to continue his observations, hoping to present the 

 Association with a more perfect list on a future occasion. 



Mr. Royle read a communication on Caoutchouc. 



Mr. P. Duncan detailed some observations on Marine Luminosity. 



Dr. Hancock read a paper " On the Cow fish, Manatus jiuviatilis, 

 of the inland waters of Guiana." 



Dr. Macartney made some observations on the preservation of 

 animal and vegetable substances from the attacks of insects. He 

 employed a concentrated solution of equal parts of alum, nitre, and 

 salt, mixed with an equal quantity of proof spirits and a little oil of 

 lavender or rosemary. A forcible injection of this liquid into the 

 arterial system would perfectly preserve a dead body for three or 

 four months fit for dissection, and portions of one which had been 

 thus injected, if rubbed over with pyroligneous acid, might be pre- 

 served for any length of time. He recommended a coat of plaster 

 of Paris to be daubed over succulent plants as a mode of preserving 

 them, and, when dry, this might be easily removed. He noticed 

 the entire preservation of some bodies found in the bogs of Ireland. 



Mr. Hope exhibited a collection of North American insects, prin- 

 cipally Coleoplera, collected from the raw turpentine sent over to 



