( «54 ) 



Avhicli luid eiitirelv fallen asunder, iind of rallier large lime-coiicretioiis. 

 This clashes with Lixnaksson's ') ojiiiiion, that at Borgholm this layer 

 shoukl consist of marl-slate only, which opinion was afterward made 

 use of by Rokaier *) and Remki-k "). 



In the said lime-concretions 1 found, l)esides some remains of 

 Pciradoxides Oelandicus Sjogren and a couple of nearly complete sj)e- 

 cimens of Ellipsocephalus Polytomus Linnaksson, countless mid-shells 

 of the latter species of Trilobitcs. 



Here was confirmed the opinion of Linnarsson '') that the absence 

 of stripes on the front-edge of the mid-shells, and that of the pricked 

 points, on the scale of tlic Ellipsocephalus -species occurring at 

 Borgholm, by which this species was said especially (o differ from 

 the Slora Frö-spccies, must be attributed to the circumstance that 

 liis Borgholm material came from marl-slate, and that of Stora Fro 

 from lime-s(one. The stripes and the i)ricked points are remarkably 

 distinct in the mid-shells I gathered from the lime-concretions at 

 Borgholm. Consequently there is no reason any more for not ranging 

 the Ellipsocei)l»alus-remains of Stora Fro under the head: Elli{)Soce- 

 phalus Polytomus Linnarsson, the difference in size only not sufficing 

 to maintain the contrary. 



One of the lime-concretions contained a layer that was ))eculiarly 

 rich in mid-shells of Ellipsocephalus Polytomus. While breaking this 

 concretion to pieces, I was immediately I'cminded of my Groningen 

 erratic-block; and now that 1 have ('om|)ai'ed the latter with the 

 pieces I brought from Borgholm, I know that they are exactly alike. 

 In both the stone is the same, exce])t that the Gi-oningen piece has 

 a yellow tint, wliicli must be attributed to the influence of corrosion. 

 The mid-shells of Elli|>socephalus Polytomus, occurring in both, also 

 resemble each other, in coloui- as well as in their numerous Haws. 



Consequently it may with })erfect certainty be declared that the 

 erratic-block mentioned above has the same age as the layer with 

 Paradoxides Oelandicus Sjogren (the oldest of the Mid-Cambrian), aiul 

 that a corresponding kind of stone is still fouiul at Borgholm in 

 Oeland. It is probably also met with at Stora Fro in the same 

 island. I cannot say so for certain, however, as I did not go there 

 and so do not possess any limestone from that })lace, which might 

 be used for comparison. 



1) Linnarsson. Om Faunan i lagren med Paradoxides Oelandicus. (Jool. Ftiienin- 

 geiis 1 Stockliolin l'"'örhandlingar. Bd. 3. pag. 351. 

 ") PiOEMF.n. Lolhaea erratica. pag. 87. 



^) Remelk. Zeilsclir. d. deutscli. geol. Gescllscliaft. Bd. 33. 1881, pag. 183, 701. 

 *) Linnarsson. Loc. cil. pag. 364. 



