396 Proceedings of Learned Societies. 



of cerium, and it was important as furnishing the only instance of 

 the occurrence of the rare metal cerium in Great Britain. The 

 other new minerals described were a hydrated phosphate of 

 aluminium and calcium, and a hydrated arseniate of copper and 

 lead. 



A communication was also made by Mr. John Hunter on the 

 absorption of vapours by the charcoal obtained from the shell of the 

 cocoa-nut. This possesses a high degree of absorbing power ; taking 

 up at the elevated temperature of 90 a Cent, no less than 155 times 

 its bulk of the vapours of methylic alcohol. 



THE ENTOMOLOGICAL SOCIETY.— Nov. 6. 



Acclimatization of British Insects in Canada. — -Mr. G. J. 

 Bowles communicated a paper on the recent naturalization and 

 rapid spread of the small white cabbage butterfly, Pieris Papce, 

 in Canada. It is presumed that the insect must have been imported 

 in the condition of eggs or pupee. Eor some seasons only a few 

 specimens were seen ; but recently the increase of their numbers 

 has been very great. As the Pieris Pajpce feeds on a vast number of 

 plants, although selecting in preference those belonging to the 

 cruciferous group, there can be no doubt that it will become a per- 

 manent addition to the fauna of the North American continent. 



GEOLOGICAL SOCIETY.— Nov. 8. 



"On the Origin of the Parallel Roads of Glen Roy." — 

 The Rev. R. Boog Watson gave a brief description of these well- 

 known " Roads," in which he analysed the two principal theories 

 that have been started to account for their formation — namely, the 

 Ice- dam theory and the Marine theory. With regard to the first 

 theory, he stated his opinion that although it has some strong 

 points, especially in respect of the coincidence between the levels 

 of the " Cols " at the glen-heads, and those of the " Roads," yet on 

 the other hand it is weak, inasmuch as the cause assigned is ex- 

 tremely local in its action, while the phenomena to be explained are 

 very general and have a wide range — terraces similar to those of 

 Glen Roy occurring in Scandinavia and elsewhere. In the author's 

 opinion, the formation of the " Roads" by an ice-dam is impos- 

 sible, for the dam would not have been water-tight, and there is no 

 period at which it could have existed during the post-Pliocene 

 changes in Scotland. Objections like these cannot be urged against 

 the Marine theory, as the sea has been on the spot, and is able to 

 perform the work required of it. At the same time the author 

 admitted that the Marine theory is not free from difficulties, the 

 chief being the perfection and horizontally of the " Roads," and 

 their barrenness in Marine organisms. 



