Sept. 1 8, 1879] 



NATURE 



'487 



taken in these sedimentary deposits by palagonites, quite identical 

 in lithological cliaracters with those of Sicily, Iceland, and the 

 Galapagos Islands. One may, in fact, call them glasses of the 

 basic series, playing the most important part among the sedi- 

 ments of the Pacific, and consisting either of sideromelane or 

 decomposed into a red resinoid substance. The small lapilli of 

 two or three inches in diameter are cemented by zeolites, the 

 crystalline forms of which are those of christianite. It is 

 enough to indicate the presence of the easily alterable basic 

 glasses, in order to show the source of the clayey matter with 

 which they are associated, since it is known that wherever rocks 

 of this type occur, there also decomposition into clay is observ- 

 able. 



Amongst the minerals present in the volcanic ash are rhombic 

 tabular crystals of plagioclase, augite, magnetite, with a little 

 sinidine or hornblende. It is also remarkable to notice that in 

 these deep-sea deposits quartz grains are practically absent, in 

 striking contrast to the coast-deposits. It is not, however, this 

 fact which is most worthy of note, since it is not so unexpected 

 .is the formations of zeolites in the free state. The latter phe- 

 nomenon takes place in the zone in question where minute 

 fibrous radiated spherules are formed in the mud, possessing the 

 crystallographic characters of christianite. Besides these zeo- 

 litic globules, there are other crystals of the same kind in the 

 form of very minute prisms, occurring in such prodigious 

 numbers that they make up about a third of the red clay. Crys- 

 tallographically these microliths must be referred to those forming 

 the zeolitic spherules. The authors regard them as belonging 

 to one species. The formation of these zeolites and of the red 

 clay in which they are developed, is easily understood if we bear 

 in mind the lithological nature of the above-described basic 

 tuffs and of their products of decomposition. 



The Geological Age of the Rocks of West Cornwall, by J. H. 

 Collins, F.G.S. — Mr. Collins endeavours to show that a large 

 area of West Cornwall, hitherto mapped as Devonian, really 

 consists of upper Silurian rocks ; lower Silurian rocks underlie 

 them, whilst a still older series occurs at several points on the 

 coast^possibly the mica schists of the Lizard belong to this 

 oldest series. 



Geological Facts observed in Natal and the Border Countries, 

 by Rev. G. Blencowe. — Mr. Blencowe describes the country 

 near the border of Zululand. The rocks are sandstone, capped 

 by trap, which often stands out in isolated hills rising 2,000 feet 

 above the plain. Evidences of ancient volcanic action are 

 noticed. 



On " Culm" and " Kulm," by Prof. G. A. Labour, M.A., 

 F.G.S. — He suggests that the English word "culm" be retained 

 as a local term for the culm measures of Devon and Somerset. 

 Under the Germanised form of the name ("kulm") are now 

 grouped a vast mass of carboniferous slaty beds which strike 

 across Europe from Eastern Silesia to the westernmost point of 

 Portugal ; tliese beds represent, not the coal measures of Eng- 

 land, but the carboniferous limestone and underlying beds. 



On some Remarkable Pebbles in the Boulder Clay of Cheshire 

 and Lancashire, by Dr. C. Ricketts. — The pebbles give evidence 

 of having formed parts of moraines on land. As they occur at 

 different horizons it is inferred that there must frequently have 

 been an advance and retreat of glaciers, moraines being formed 

 during the retreat of the glacier, which were carried forward 

 into the sea when the glacier advanced. 



Notice of the Occurrence of a Fish Allied to the Coccosteus in a 

 Bed of Devonian Limestone near Chudleigh, by J. E. Lee, F.G.S. 

 — This occurs (in the upper or middle Devonian) with clymenia, 

 ijoniatites, and crinoidal remains, and therefore cannot here be a 

 freshwater fish. 



Evidence of the Existence of Pahcolithic Man during the Glacial 

 Period in East Anglm, by Sydney B. J. Skertch'ly, F.G.S., 

 H.M. Geological Survey.— The object of this paper is chiefly to 

 record the sections in which the author has discovered pala;olithic 

 implements beneath the chalky boulder clay in East Anglia. 



The beds which yield the implements are a series of loams, 

 clays, and sands, to which the author has given the name of 

 lirandon Beds. They occur at the top of the middle glacial 

 series of Messrs. S. V. Wood, jun., and F. W. Ilarmer, and 

 underlie the chalky boulder clay or upper glacial of the above- 

 named authors. 



On Carboniferous Polyzoa and Palaocoryne, by G. R. Vine. — 

 In this paper the author drew attention to the inadequate study 

 that had been given to the carboniferous Polyzoa. During the 

 last few years vast masses of shales, containing Polyzoa and 



other remains have been brought to light, but none that he 

 was acquainted with excelled in richness the Hairmyres debris. 

 Here the specimens were well preserved and the characters of 

 the several species were almost perfect. 



The author considered that it was too early yet to draw up a 

 classification that would be satisfactory to]aU naturalists. Attempts 

 had been made to do this, but many details had to be furnished 

 that could only be furnished after close study. Besides the 

 Fenestella, other genera were alluded to in the paper, such as 

 Cenopora, Rhabdomeson, Hyphasmapora, Glauconome, and Dias- 

 topora ; but these are being studied analytically, and further 

 details of their structure will be brought forward in a future 

 report. 



Palaeocoryne was next alluded to, and the author said that 

 he had identified all the species and forms of Palaeocoryne 

 that had been figured by Dr. Duncan in his various papers ; but 

 the conclusion the author had arrived at was — that these so-called 

 organisms were neither hydroid, as was supposed by Dr. Duncan, 

 nor foraminiferal, as was suggested by Dr. AUman. All the 

 forms were referable to species of Fenestella and Polypora. 

 Although this opinion was given with some confidence the author 

 was not prepared to say at present that the whole of Dr. 

 Duncan's views were illusive. There can be no doubt bat that 

 the forms P. scotica were really infertile processes ; but P. radiata 

 had presented so many peculiar details to the author, that until 

 he had satisfied himself as to the nature and purpose of this 

 structure in the polyzoary of the Polyzoa, he was not pre- 

 pared to substantiate that Dr. Duncan had given an erroneous 

 judgment, although P. radiata may turn out to be after all a 

 portion of Fenestella and not a parasite. 



On the Replacement oj Siliceous Skeletons by Carbonate of Litnt, 

 by W. J. SoUas, M.A., F.G.S., &c. — The author gave an ac- 

 count of certain calcareous fossil remains which exhibit, both in 

 gross and minute structure, a close resemblance to certain exist- 

 ing siliceous sponges, and which differ widely from any known 

 form of calcareous sponge. The natural inference appeared to 

 be that the calcareous fossils were once siliceous sponges, the 

 siliceous parts of which had undergone replacement by carbonate 

 of lime. The alternative view that the fossils were originally 

 calcareous, and that they represent an extinct group of Calci- 

 spongia, was discussed and shown to present far greater difficul- 

 ties to the zoologist than the inferred mineral replacement 

 offered to the chemist. Siliceous sponge spicules were stated to 

 be remarkably soluble, yielding readily to the attacks of minute 

 boring algos, and undergoing solution in sea-water soon after the 

 death of the sponge which possessed them. 



The radiolaria of the carboniferous limestone were likewise 

 regarded as having once possessed a siliceous composition, which 

 they had since exchanged for a calcareous one. 



On the Foundations of the Town flail, Paislev, by M. Blair. — 

 Dolerite underlies the boulder-clay there, and is probably the 

 source of boulders of a similar rock which occur in the drift, 

 and which have hitherto been considered as strangers to the 

 neighbourhood. 



On " Ostrakocanthus dilatatus" {gen. et sp. nov.), a Fossil Fish 

 from the Coal- Measures South-east of Halifax, in Yorkshire, 

 by J. W. Davis, F.G.S. — This is an ichthyodorulite nearly I j 

 inches long, and } inch broad at the base. From the base the 

 diameter diminishes rapidly, and at half an inch from the apex 

 it is only '15 of an inch. It remains of this size to the apex, 

 and ends in a blunt point. The upper part is smooth, with hard 

 ganoid covering. The lower part is longitudinally furrowed, 

 increasing by bifurcation towards the basal end. At first sight 

 it somewhat resembles the Byssacanlhus of Agassiz, and also 

 the spine of Ostracion corniitus, but the similarity disappears on 

 closer examination. From the spine and its mode of attachment 

 it is probably a representative of the Teleosteans during the coal 

 period. 



SECTION D— Biology 



Department of Zoology and Botany 



On the Capreolus or Spermatophore of some of the Indian Species 

 of the J/elicidie, by Lt.-Col. II. II. Godwin- Austen, F.Z.S., 

 &c. — The author points out the importance of the examination 

 of the animal in many genera of the Ilelicidne, and thus to obtain 

 better characters for specific distinction than are often presented 

 by the shell alone. The organ first discovered and described by 

 Lister in 1694 is treated of, and the views of later naturalists al- 



