1846.] MURCHISON ON THE GEOLOGY OF GOTHLAND. 25 



Gothland; but whether transported thither, or simply misplaced 

 and mislabelled in a museum, it must, after the preceding descrip- 

 tion, be obvious to every geologist that no such fossil can have 

 had a place in the rocks charged with the true Upper Silurian 

 forms which are found throughout the southern mass of Gothland, 

 extending from Bursvik on the north to Hoburg Point on the 

 south. 



Hoburg Head, though not the mountain spoken of by Linnaeus 

 (for it seemed to us at no point to exceed 200 feet in height), is 

 still a bluff bold headland, particularly when viewed on its southern 

 and western faces, which are washed by the seaf. 



Its lower strata, as represented in the diagram (PI. I. fig. 12, 2), 

 consist of the sandstone above-described, only visible at low tides in 

 the form of flag and tile-stones ; the lower beds of sandstone rising 

 to the north being only apparent a little to the north of the Hoburg 

 Head, where they are quarried. The next stratum (z*) is a small 

 concretionary limestone, representing in a very coarse form the piso- 

 lite and oolite of Bursvik and Grotlingbo, and containing some of 

 the same fossils. The rock marked (K) is a mass of coralline lime- 

 stone, a perfect breccia or plexus of corals with earthy partings forty 

 feet thick : among other shells we found in it the Avicula retrqflexa 

 of the inferior pisolite also in this band. The next stratum (^*) is 

 an encrinite limestone forty feet thick, with few or no corals. This 

 uppermost stratum is a hard marble of red, greenish or greyish and 

 white colours. 



The limestone of Hoburg, which unquestionably overlies the sand- 

 stone and pisolite of Grotlingbo and Bursvik (fig. 11) as seen in 

 various hills of this southern peninsula in the parishes of Vamlingbo 

 and Sundre, certainly contains two or three species of shells and 

 numerous corals identical with those of the north of Gothland. But 

 the great mass of the Wenlock shells are no longer found in it, their 

 place being taken by other species ; whilst the corals Catenipora 

 escharoides and CdahyrintJdca, so characteristic of the inferior strata, 

 no longer appear. It is also to be observed, that in addition to the 

 Ludlow fossils J above-mentioned, we here find the Leptcena Fis- 

 cheri (nob.), a species belonging to the unquestionably Devonian 

 system of Russia. 



Considering then the order of succession and the fossiliferous con- 

 tents of this southern promontory of Sweden, I must beg to differ 

 from those who have previously visited it, including my distinguished 

 associate in the Imperial Academy of Sciences of St. Petersburg, 

 Colonel Helmersen, who preceded us in our last summer's survey. 

 Seeing that the limestone of Hoburg Head was very full of certain 

 species of Upper Silurian corals, and even contained two or three 

 species of shells similar to those of the central and northern parts of 

 this island, he, in common with previous authors, concluded, — 1st, 

 that the chief calcareous mass of the island is everywhere identical ; 



t It has a fine cavern on one of its northern faces. 



X A specimen of Homalonotus has also been found in the Hoburg promontory, 

 and is to be seen at Copenhagen. 



