April 13, 1888.] 



SCIENTIFIC NEWS. 



355 



gested that while this might be to some extent due to 

 differences in composition, it was more probably owing 

 to differences of nodular constitution. He considered it 

 unnecessary to refer to the action of humic acid, because, 

 while the salt to which the solvent action is attributed 

 would be capable of doing such work, and would be 

 probably abundant in the region referred to, we could 

 not expect any great amount of humic acid in the same 

 area. 



On the Probable Mode of Transport of the Frag- 

 ments of Granite and other Rocks which are found im- 

 bedded in the Carboniferous Limestone of the neighbour- 

 hood of Dublin. By Prof. V. Ball. 



Angular fragments of granite and of schist, quartzite, 

 and vein-quartz, such as might have been derived from 

 the metamorphosed rocks which rest on the granite near 

 Dublin, have been discovered in beds of carboniferous 

 limestone, which often contain fragments of fossils, 

 especially Encrinites. They have been previously 

 noticed by Professor Haughton, Mr. H. B. S. Montgomery, 

 Prof. Jukes, and Mr. Croll. While Prof Jukes refers 

 their transportation to the agency of land-plants, Mr. 

 Croll quotes their occurrence in support of his argument 

 as to the existence of glacial conditions during the 

 carboniferous period. 



The author observed that the specimens exhibited 

 none of the indications of the existence of glacial con- 

 ditions, whether we regard the characters of the 

 boulders or the nature of the rock in which they are 

 imbedded, which contains no such silt as that occurring 

 in the boulder-bed of the Talchir formation. Whilst 

 rejecting the view that they were transported by ice, he 

 pointed out that they need not necessarily have been 

 carried by land-plants, but that they might have been 

 torn from the sea-floor by marine alga;, some .of which 

 may have had a more buoyant character than those of 

 modern seas. He cited the case of a sandy beach in the 

 neighbourhood of Youghal, which is strewn with lime- 

 stone fragments, which had been conveyed by sea-weeds 

 thrown up after storms from submarine banks. 



It was suggested that the occurrence of natural fissures 

 in the rocks and cracks produced by concussions from 

 large masses hurled about by the waves might sufficiently 

 explain how the fragments could be freed from the main 

 mass of the reefs under the stress of the waves. 



The Upper Eocene, comprising the Barton and 

 Upper Bagshot Formations. By J. Starkie Gardner, 

 Esq., F.G.S., and Henry Keeping, Esq., with an Appendix 

 by H. W. Monckton, Esq., F.G.S. 



The familiar Upper Eocene having been transferred to 

 the Oligocene, the remaining uppermost division of the 

 Eocene bears the title Middle. Unless the considerable 

 literature relating to the Brackleshams, the Calcaire 

 Grossier, and the Nummulitic is to be rendered obsolete, 

 their classification as Middle Eocene must be preserved, 

 and a modified Upper Eocene constructed out of the 

 Barton series. 



The base of the formation is not sharply defined, but 

 it coincides with the final disappearance of several sub- 

 tropical Mollusca, and almost with the extinction of 

 Nummulites in our area. The upper limit is drawn at 

 the base of the Lower Headon, where the brackish fauna 

 gives place to one of fresh water. 



The conditions of deposition were examined at some 

 length, and evidence in support of the estuarine origin of 

 the formation was adduced. The fauna of the Lower 



Barton division comprises many Bracklesham species, 

 which range no farther up, and a large numlser of 

 peculiar species. The most convenient base-line for the 

 Middle Barton is the lowest of several bands of Septaria, 

 which distinguish the 50 feet of drab clays which are 

 comprised in it. The finest Barton fossils are obtained 

 from the Middle division ; but though so many splendid 

 species characterise it, few are absolutely confined to it. 

 The upward range of a further number of Bracklesham 

 species ceases at the shell-bed. The Upper Barton in- 

 cludes the Chama-hed, the Becton Bunny, and the Long 

 Mead End beds. 



Mr. Monckton, in his Appendix, stated that in the 

 London basin the Barton beds are represented by the 

 Upper Bagshot Sand, a mass of yellow or nearly white 

 sand without clay-beds, though often loamy. Its greatest 

 proved thickness is 2 28| feet, and the base is marked by 

 a very persistent bed of pebbles. 



Its extent is considerably greater than is shown on the 

 Geological Survey map. 



Casts and impressions of shells are abundant in some 

 places, but recognisable species have only been found at 

 Tunnel Hill, near North Camp Station, Aldershot. A 

 large collection from this place has been made by Mr. 

 Herries and by the author. 



SOUTH LONDON MICROSCOPICAL AND 

 NATURAL HISTORY CLUB. 

 At the February meeting of this club. Dr. M. C. Cooke 

 read a paper on " Horny House Builders ; or, Zoo- 

 phytes." 



The author said an enthusiastic naturalist had published 

 an interesting record of his rambles, including trips by boat 

 off the Sicilian coast, where, in an absolute calm, with the 

 surface of the water as smooth as a mirror, the eye was 

 permitted to observe in detail the various forms of 

 marine life at an almost incredible depth. Among the 

 things to be seen were little shrub-like structures, every 

 bud and spur of which was an animal. Few had been 

 privileged to see these plant-animals flourishing in their 

 native seas, but all had been made acquainted with their 

 skeletons, or, more happily, their deserted houses, when, 

 torn from the rocks by storms, they were cast upon the 

 beach. It was hardly surprising that in days gone by 

 these organisms — by some incorrectly called corallines — ■ 

 should be regarded as sea-plants or weeds, and when 

 their minute structure and method of life were unknown, 

 it was quite excusable that such mysterious "toilers of 

 the sea " should be deemed vegetable in nature. Now, 

 however, when their inmost secrets had been revealed, 

 no one would hesitate to pronounce them animals. That 

 portion of the colony which was permanent was the 

 branched horny tubes. The little animals were contained 

 within these branches, and soon died when removed 

 from their native element. The material of which 

 the sheath was formed was called " chitine " — a sub- 

 stance that differed from horn in its chemical compo- 

 sition. There were many forms of these animals. Some 

 preferred shallow, others deep water ; some attached 

 themselves to the rocks or the larger sea-weeds ; and, 

 again, some of the smaller were parasitic on the larger 

 species. The animals resembled fresh water hydrac, 

 united together into branched colonies of some hundreds 

 of individuals, and located, like the lodgers in a model 

 lodging-house, within one common home. It was a 

 beautiful sight to see one of these branched colonies 



