Jan. 2 1, 1 886 J 



NA TURE 



285 



and smell), and the reporting of the same to the nervous cen- 

 tres of the animal, from whence the intelligence is sent out to the 

 spines and pedicellaris, which latter are at once alert to secure 

 the food-substance. — The nerve-terminations in the cutaneous 

 epithelium of the tadpole, by A. B. Macallum (plate 6). The 

 results are summarised as follows : — (l) Certain fibres of the 

 nerve network, situated below the cerium, and known as the 

 fundamental plexus, give origin to fibres which enter the epithe- 

 lium, and terminate in comparatively large bead-like bodies 

 between the cells. (2) From a network of fine ana^tomising 

 nerve-fibrils situated immediately below the epithelium, and 

 forming meshes, each narrower than the surface covered by an 

 epithelial cell, arise other e.xcessively fine fibrils, which end 

 either within or between the cells or after branching, in both 

 fashions. (3) One, commonly two, often three or more, nerve- 

 fibrils terminate in the interior of each epithelial cell near its 

 nucleus. (4) The figures of Eberth are sheaths for intracellular 

 nerve terminations. — On green oysters, by Prof. E. Ray Lankes- 

 ter (plate 7). The occurrence of a species of Navicula in the 

 intestine of the green oysters of Marennes, is confirmed. The 

 bluish pigment in the Navicula is described as " Marennin." 

 The description and illustration of the secretion-cells of the 

 epithelium of the branchia* and labial tentacles of the oyster in 

 which the Marennin absorbed in the intestine of green oysters 

 is deposited follows, and it is proved that it is to this substance 

 that the green parts owe their colour. The green oyster is very 

 beautifully figured, of natural size, from a sketch by Miss 

 A. Stone. The bluish pigment is, in the early spring, of a de- 

 cidedly green hue. — The system of branchial sense-organs and 

 their associated ganglia in Ichthyopsida : a contribution to the 

 ancestral history of Vertebrates, by Dr. John Leard (plates 

 8-10). 



American y ouynal nj Science, December 1SS5. — On the effect 

 on the earth's velocity produced by small bodies passing near 

 the earth, by H. A. Newton. It is shown that the effect upon 

 the earth's motion caused by the meteors that penetrate the 

 earth's atmosphere, exceeds at least one-hundredfold that 

 caused by the meteors that pass by without impact. — Sources of 

 trend and crustal surplusage in mountain structures, by Alex- 

 ander Winchell. The general meridional trend of the older 

 mountain systems is discussed, and the cause of this orographic 

 disposition is referred to the early period of incrustation. It is 

 also argued that meridional trends would be further promoted 

 by the secular subsidence of the earth's equatorial protuber- 

 ance, as well as by lunar tidal action. — The genealogy and ihe 

 age of the specie> in the Southern Old Tertiary, pari iii., reply 

 to criticisms, by Otto Meyer. In reply to Prof Hilgard, the 

 author maintains with (uither argument the original contention 

 that only a competent and careful examination of the tessils 

 could indicate the relations of the Old Tertiary strata of 

 Mississippi. He also endeavours to show that Prof. Hilgard's 

 views on the stratigraphical succession below Claiborne, Jackson, 

 and Vicksburg are incorrect. — The condensing hygrometer and 

 psychrometer, by Henry A. Hazen. Objections are raised 

 against the condensing hygrometers now in use, such as those of 

 Mr. Dines and Crova. An efficient psychrometer is described, 

 with instructions for its use, and a table of relative humidity 

 applicable to the sling psychrometer. — A new form of absorp- 

 tion cell, by Arthur E. Bostwick. The cell here described has 

 been devised and used by the author for the purpose of obtain- 

 ing the absorption-spectra of liquids, which have little selective 

 absorption, and which would therefore have to be used ordinarily 

 in large quantities. — Preliminary notice of fo-sils in the Hudson 

 River slates of the s^uthern part of Orange County, New 

 York, and elsewhere, by Nelson H. Darton. Here the author 

 deals with the fossils discovered in many new localities, 

 which have thrown much light on the complicated strati- 

 graphic structure of these districts. — Report of the Ameri- 

 can Committee-Delegates to the Berlin International Geo- 

 logical Congress, held September 28 to October 3, 18S5, by 

 Persifor Frazer, Secretary.— Bright lines ii stellar spectra, by 

 O. T. Sherman. Bright lines hitherto admitted to form part of 

 but six stars, ^ Lyra;, 7 Cassiopeite, and four small stars in 

 Cygnus, are now detected by the S-i .ch equatorial of Yale Col- 

 lege Observatory in numerous other stars, a full descripti;n of 

 which awaits the completed apparatus. The number of approxi- 

 mate coincidences renders it very probable that the lines ob- 

 served ar.' those of the solar atmosphere, and from these 

 observations it would seem that there are many stars in the same 

 condition as the sun, but with the corona more pronounced. — 



Note on the o]ilical properties of rock-salt, by S. P. Langley. 

 The most perfect r.. ck-salt jirisms procurable in Europe fail 

 to show distinctly a single Frauenhofer line. But, after long 

 searching, blocks have at last been obtained in America, from 

 which prisms have been cut which show these lines with all the 

 sharpness of flint glass. The prism here described, which has 

 been made by Brashear of Pittsburgh, shows the nickel line 

 between the D's. 



SOCIETIES AND ACADEMIES 

 London 



Royal Society, December 17, 1885. — "Second Report on 

 the Evidence of Fossil 1 lanis regarding the Age of the 

 Tertiary Basalts of the North-East Atlantic." By J. Starkie 

 Gardner. Communicated by Sir J. D. Hooker, K.C.S.I., 

 F.R.S. 



The position and physiography of this headland in the Isle of 

 Mull has been fully described by the Duke of Argyll. It is the 

 point of land separating Loch Laigh and Loch Scridain, and is 

 about two miles in circumference and a mile across. 



It is composed mainly of two sheets of basalt with remains of 

 a third sheet, on some eminences and along the shore of Loch 

 Laigh. These are almost horizontal, with a slight dip east, u]i 

 Loch Scridain, and a considerable dip in the same direction up 

 Loch laigh. The upper sheet is not less than 40 to 50 feet 

 thick, crystallised into rude massive columns, now much fissured 

 and weathered, whilst the lowest presents a thickness of 60 feet, 

 visible above low water, the upper two-thirds being amorphous, 

 and the rest fashioned into slender and most perfect columns, 

 bent in every direction, like those of the Clam-shell cave at 

 Staffa. The beds are so exceedingly horizontal towards the 

 seaward direction, that no one can doubt the columnar basalts 

 of Staffa and the Treshnish Isles, Geometra and the mainland 

 of Mull, being on the same horizon, if not parts of the same 

 sheet. Between the two great lava- beds at Ardtun is intercal- 

 ated a bed of sedimentary deposit, reaching a maximum of 

 60 feet thick, and consisting of pale veiy fine-grained clay and 

 limestone at the base, then sand and gravel, black laminated 

 shales, whinstone, gravel, and laminated sands. The gravels 

 are made up of flint pebbles and subangular rolled fragments of 

 older lava-beds in. a matrix of broken-down volcanic material. 

 They present all the ordinary lines of current bedding, beauti- 

 fully weathered out, and the pebbles are drifted precisely as in 

 ordinary river gravels. 



There can be no question whatever, indeed, but that the 

 gravels are the deposits of the waterway of a river of some 

 magnitude, and the shales its overflows and backwaters. Its 

 deposits traverse the whole seaward face of the headland, and 

 their extension inland is marked by two beds of coal. An in- 

 trusive sheet of fine compact basalt rises on one side of the 

 head, cutting a devious way through each bed in turn, and dip- 

 ping beneath the sea at the other extremity. On the coast, 

 near the centre of the head, occurs a small chine, apparently 

 due to the weathering out of a vertical dyke, which has cut 

 through the gravels and shales ; it was here that I resolved to 

 excavate them. 



With the assistance of a barrel of powder and the removal of 

 a mass of the intensely indurated shingle bed, to the extent of 

 perhaps hundreds of tons, many square yards of the whinstone 

 and the underlying black shales were exposed. The large speci- 

 inens of Platanites aecroides and Ouoclea lieiridica, now ex- 

 hibited, were the results. The ravine, however, proved an 

 unfortunate selection, for the whinstone became poorer in fossils 

 as we got farther in, and the underlying black shales, though 

 crowded with leaves, were so squeezed and full of slickensides 

 or faulted surfaces, and, consequently, so brittle, as to be practi- 

 cally valueless. From the condition of the shales and calcined 

 appearance of the gravels — here of a steely-gray colour, intensely 

 hard, with pure white and occasionally cheny-coloured flints, it 

 is evident that the ravine must be the site of an old dyke, and 

 if proof were wanting of a violent upthrust at this spot it is to 

 be found in the upturned edges of the bottom bed on the west 

 face. The succession of beds in the section we had been so 

 laboriously working at in the ravine in no way prepared me for 

 the discovery that within 100 yards there existed, many feet 

 below the lowest sedimentary bed present in the ravine, a 

 deposit of limestone, rivalling in fineness and texture the cele- 

 brated lithographic stone of .Solenhofen, and containing ex- 



