SCIENCE-GOSSIP, 



35 



the most striking evidence is that of the Car- 

 boniferous ice age in India. For in that formation 

 pohshed and striated boulders have been found 

 strikingly similar to those of the Great Ice Age. 



Before the Glacial period proper, however, Mr. 

 Manson thinks that local glaciation may have 

 taken place on some of the older mountains, to 

 disappear again by the setting free of earth heat 

 by vast fractures of the crust. This, he believes, 

 satisfactorily accounts for apparent Glacial and 

 Interglacial periods in the past. Whether, how- 

 ever, Mr. Manson' s theory permits the supposition 

 of a Glacial period so far back as the Carboniferous, 

 appears more than doubtful. 



It is evident, again, that according to this theory 

 glaciation must have extended from pole to pole ; 

 and the objection is at once apparent, that in the 

 northern hemisphere we have evidence of glaciation 

 only as far south as latitude 50° in Europe, and 

 40° in North America. 



The various conditions of climate while the 

 earth was under the control of its own internal 

 heat were, an era of torrid heat, an era of 

 tropical heat, an era of temperate heat, an 

 era of glacial cold. It was during the era 

 of torrid heat, when the surface temperature had 

 sunk to 90° P., that the luxuriant vegetation of the 

 Carboniferous period appeared and clothed the 

 world from pole to pole. Palaeontology, however, 

 has not shown corresponding changes in the life of 

 the globe. Yet it is contended that the fossil life 



of deposits below the Permian belongs to an ultra- 

 tropical type, while that of Mesozoic times is 

 tropical in character. While during Tertiary times 

 a temperate climate up to the poles is said to be 

 indicated by the Tertiary fossils of Greenland, 

 Spitzbergen, etc. ; glaciation would commence the 

 moment a snow flake reached the earth which its 

 waning heat was unable to melt. Going back 

 to Archaean times, Mr. Manson considers the crys- 

 talline character of the rocks proves the high 

 temperature then existing on the earth. 



It may be useful here to add Mr. Manson's own 

 recapitulation of his paper. " The objects of this 

 paper are to demonstrate : (i) That in the passage 

 of the earth from an era during which its climates 

 have been controlled by internal heat, into an era 

 during which its climates are controlled by solar 

 heat, a Glacial period must intervene. (2) That 

 the direct cause of the Glacial period was a 

 combination of the remarkable properties, in 

 relation to heat and cold, possessed by the various 

 forms of water : as vapour, it prevented the loss 

 or receipt of heat by radiation ; as water, by reason 

 of its high specific heat, it retained to the last 

 moment the effective remnant of earth heat ; as ice, 

 it assumed a solid form, storing the maximum 

 amount of cold. (3) That through all geological 

 time to the culmination of the Glacial period, 

 solar heat was only conservative of earth heat." 



29, Queen's Terrace, Jeimond, 

 N ewcastle-on-Tyne. 



LANCASHIRE COAST MOSSES. 



By J. A. Wheldon. 



OPRING is not the best time of the year for the 

 botanist to visit the Lancashire sand-dunes ; 

 but I had promised Messrs. Dixon and Bonlay 

 additional specimens of an apparently new variety 

 of Hypnum aduncum, which I found there last 

 autumn ; therefore, on a gloriously fresh May 

 morning I set forth with my son in search of a 

 further supply of the novelty. En route we passed 

 the new Lancashire locality for Catharinea undulata 

 var. haushnechtii Dixon. We succeeded in finding 

 a few old capsules still persisting, their setae 

 having become lateral through lengthening of the 

 axis by means of innovations near the apex. An 

 adjacent pond was white with abundance of Ranun- 

 culus aquatilis, relieved by an occasional patch of 

 yellow Caltha palustris, the shallower margins being 

 choked with a tall floating form of Hypnum riparmni. 

 This is a most protean moss, which sometimes 

 simulates a humble creeping Brachythecium, and 

 anon resembles a huge Fontinalis or one of the 

 harpidioid forms oi Hypnum. 



Not far from this pool is a station for Cochlearia 



danica. It has been asserted that this species does 

 not occur on the Lancashire coast, but I have 

 found it in some plenty here, and more sparingly 

 to the north of Southport. The Rev. E. F. Linton 

 has kindly examined and verified fresh specimens, 

 thus confirming the opinion previously given by 

 Messrs. Marshall and Beeby from dried examples 

 which I had sent to the Botanical Exchange Club. 



From the train which bore us to our destination, 

 we noticed the sand-martins busily excavating the 

 perpendicular walls of a red-sand quarry, and the 

 railway banks were gay with the flowers of Scilla 

 nutans, Lychnis dioica and Erysimum alliaria. 



On arrival at Southport we soon deserted the 

 smiling flower-beds of the foreshore for the arid- 

 looking dunes, which were anything but barren to 

 us, as we were speedily surrounded by interesting 

 objects on all sides. Even the loosest drift sand 

 was spangled with the flowers of the dandelion, 

 both the varieties laevigatum and erythrospermum 

 being equally common, but when the former is 

 waning in glory the latter just attains its maximum 



C 2 



