390 



THE GEOLOGIST. 



lepis had been presumed to be^ a congener of Asterolepis, and perhaps 

 rightly so ; but we knew too little of the family of Dendrodic Celocanths 

 to justify us in regarding any one as a central type. From the investiga- 

 tion he had lately made into the fish-bearing sandstone of Elgin, he was 

 convinced that enough material might be got together, with a moderate 

 expenditure of time and trouble, to elucidate the true character, form, and 

 proportions of Bothriolepis, so long an enigma in fossil ichnology. The 

 studies of Professor Harkness in the physical history and relative position 

 of this most interesting series of sedimentary deposits ought, and probably 

 would, draw the attention of geologists in general to deposits which, 

 though possessing local characters, were yet of world-wide value, as giving 

 solutions to questions which rocks far distant had given rise to, and for 

 which Continental geologists had long asked in vain. 



On a New Starfish (Cribellites carbonarius) from the Moun- 

 tain Limestone of Northumberland. By Mr. George Tate. — The paper 

 commenced by noticing its association with carboniferous plants. Pre- 

 viously no species of Asteroidea had been recorded from this formation. 

 The specimen exhibited, found by Mr. W. Wilson, of Shilbottle, was an 

 impression of the upper surface only of the organism, in a yellow, fine- 

 grained, micaceous sandstone, and, although imperfect, was doubtless a 

 sea-star, and, as the first discovered in the formation, it deserved the at- 

 tention of paleontologists. The following characters could be observed : — 

 Kays five, rounded, lanceolate, five times as long as the disk, ridged in the 

 centre, covered with longitudinal rows of reticulating tubercles ; disk 

 small and tuberculated. The disk was only *3 of an inch in diameter, 

 whilst the rays were 1'5 inch in length. The sandstone from which 

 this sea-star was obtained was about 20 feet above the Shilbottle coal, 

 and about 10 feet below the " 18-foot limestone," which was the fifth 

 limestone sill in the mountain limestone of Northumberland ; it was, he 

 estimated, about 600 feet below the base of the millstone grit, and, as the 

 formation was about 3000 feet in thickness, it was in the upper part of 

 thi • series of beds. The paper proceeded : — " Besides the sand-star, there 

 occur in this sandstone StropJiomena crenistria and the remains of plants. 

 This association is of some interest. Numerous marine organisms in the 

 limestones and in shales connected with them, belonging to the moun- 

 tain limestone of Northumberland, abundantly evidence the deposition of 

 such beds under marine conditions ; but rarely are marine organisms seen 

 in the sandstones which form a large proportion of this formation in 

 Northumberland. Another sandstone higher up in the series, appearing 

 in a quarry, exhibits, however, a similar association. This sandstone, 

 which is 23 feet in thickness, has a thin layer, one foot thick, which is 

 crowded with StropJiomena crenistria ; but, both in the beds above and 

 those below it, there are many fragments of carboniferous plants of the 

 genera Sigillaria, Lepidodendron, Calamites, Knorria, and the Stigmaria 

 ficoides. These cases prove, the author thinks, that some of the sand- 

 stones of the mountain-limestone of Northumberland were deposited in 

 shallow bays of the sea, in which marine organisms lived, and into which 

 were drifted plants which grew during the carboniferous era. These facts, 

 however, do not invalidate the conclusion that coal was formed of plants 

 which grew on the places where coal-beds are now found, for even in the 

 Northumberland mountain-limestone formation each coal-seam rests on 

 an under clay, which was the muddy and probably swampy soil in which 

 the carboniferous flora grew. Sometimes a limestone, with marine fossils, 

 overlies a coal-seam ; but we never find a limestone or calcareous bed with 

 marine fossils lying below it." The paper then noticed other beds that 



