( 570 ) 



stone of which this erratic-block consists is coloured a strong green. 

 This is the case with some laj'ers espeeiallv. Some particles of a 

 light-colonred kind of glimmer are found in it. 



My attention was drawn to this kind of sandstone, l)ecanse, ^vlien 

 splitting this erratic-block into two parts, I found that it contains 

 Hyolithus-remains, \iz. grey -coloured stone-kernels. The lower part 

 of one of them is l)ro\vn. 



When visiting the Natural Historv-Museum at HamV)urg last sum- 

 mer, and admiring its collection of sedimentary erratic-blocks, I asked 

 Prof. GoTTSCHE whether he knew of suchlike erratics. Prof. Gottsche 

 tliought he remembered such pieces to liave been found in the sur- 

 roundings of Hamburg. Owing to want of exposing-room, however, 

 thev lav packed up among other pieces, in consequence of which 

 they could not be shown me. He drew my attention to the fact tiiat 

 in this kind of erratic-blocks sometimes occur siuall conical valves 

 of horn-shelled Brachioi)<)des. These vah'cs wei'e sllo^^ n to me in a 

 broAvn-colonred erratic-block. 



A short time after I found on the beacii at Horgholm in Geland 

 not only an erratic-block with Hyolithus-rests entirely corresponding 

 with my Hemelum piece, but also a brown piece of sandstone Avilh 

 a vahe of a small horn-siielled Brachiopode. 



1 searched my books for anytiiing on the subject of this kind of 

 erratics or stone, but at tirst without any result. 



As Prof. MoBERG at Lund in tlie summer of 1901, when I had 

 requested him to be so kind as to give me some information con- 

 cerning Geland, had noted down on my map of this island that on 

 its coast, to the North of Fiirjestaden, occur erratic-blocks with Dis- 

 cinella Holsti (then unknown to me), and the valves of Brachiopodes 

 I had found were, like those of Discina, horny and flat-conical, but 

 much smaller, I supposed that Prof. Moberg could give me some 

 information about this stone. For this reason I intended to write to 

 him concerning this subject, and, was going to do so, when acci- 

 dentally I discovered in the essay of Holm ') on the Swedish Hyoli- 

 thidae and Conulariidae, that by Moberg ') a greenish kind of sand- 

 stone, rich in Glauconites, with Discinella Holsti Moberg and Hyoli- 

 thes, occurring as erratic-blocks in Geland, had been described. 



Having studied Moberg's essay, I find that the stone of which my 



1) Holm. Sveriges Kambrisk-Siluriska Hyolithidae och Conulariidae. Sveriges 

 Geologiska Undersökning. Ser. C. No. 112. 



2) Moberg. Om en nyupptackt fauna i block of kambrisk sandslen, insammlade 

 of dr. N. 0. Holst. Geologiska Föreningens i Stockholm Förhandlingar 1902. 

 No. 142. Bd. 14. Haft 2. p. 103. 



