70 Proceedings of Philosophical Societies. [Jan.. 



firmation of them is announced and explained. M. Fries, in his 

 Systeraa Mycologicum, published last year, observes lavys of the 

 same kind to obtain in the natural arrangement of fungi, which 

 Mr. Mac Leay had pointed out as existing in the animal king- 

 dom, and as probably extending to all organized beings. In the 

 course of the paper, the difference between affinity and analogy 

 was philosophically examined and defined. Some observations 

 were also made oil the law of continuity as far as it regards 

 organized nature ; in these was shown the distinction between 

 salt us and hiatus, which have usually been confounded even by 

 the first metaphysical writers. It was remarked that no sallas 

 ever existed in nature, and that where there were hiatus, they 

 had arisen from the extinction of species. Towards the conclu- 

 sion, it was stated, that M. Decandolle had likewise observed 

 the general laws of natural arrangement which formed the sub- 

 jects of the paper ; so that these laws had thus been presented 

 to three individuals, in different countries, nearly at the same 

 period of time. 



Dec. 3. — A Description of some Insects which appear to exem- 

 plify Mr. W. S. Mac Leay's Doctrine of Affinity and Analogy ; 

 by the Rev. W. Kirby, FRS. and FLS. was commenced. 



Dec. 17. — Mr. Kirby 's paper was concluded, and another by 

 the same entomologist, entitled, " Some Account of a new Spe- 

 cies of Eulophus (Geoffroi)," having also been read, 



The Society adjourned to Jan. 21, 1823. 



GEOLOGICAL SOCIETY. 



Nov. 1. — A letter was read from W. C. Trevelyan, Esq. MGS. 

 addressed to Prof. Buckland, VPGS. on the Geology of the 

 Ferroe Islands, dated Copenhagen, Dec. 3, 1821. 



Mr. Trevelyan observes, that the Ferroe Islands appear to be 

 of the same formation as that of Antrim and of the Western 

 Islands ; they are literally mountains surrounded by water, and 

 are composed of numerous alternations of almost all the varieties 

 of trap, which are so regular, that the hills appear as if they 

 were divided into a number of terraces : most of the beds are 

 divided from each other by others (generally thin), of a red 

 colour (sometimes green), perhaps the clay ironstone of Werner. 

 These beds Mr. Trevelyan thinks have not been remarked in 

 other formations; neither a curious lava-like appearance, which 

 is very frequent, and the alternations extend to the height of 

 about 3000 feet, and in some parts, perpendicular sections may 

 be seen of more than 2000 feet high. The rocks on decompos- 

 ing are seen to be stratified ; the strata display surfaces gene-' 

 rally even, but sometimes waved. ■ Excepting in the island of 

 Myggeneas, the dip appears to be the same throughout. In 

 that island are some thin veins of coal. In Suderoe, a coal 

 similar to the Scotch, but superior, occurs in abundance; the 

 best sections of this are near Frodboe, where it is seen between 



