HARDWICKE'S SCIENCE-GOSSIP. 



21 



r.G.S. — This was the subject of a paper recently read 

 before the Geological Society of London. The author 

 commenced by explaining a section in a cutting at 

 Booth-lane Station, in which most of the beds seen 

 about Liverpool are typically represented. He then 

 gave a list of the localities in which shells were 

 found, and stated that in all forty-six species had 

 been met with, distributed through the clay-beds, 

 those found in tlie sand-seams being rare and gene- 

 rally fragmentary and rolled. The shells most com- 

 monly found entire are usually of small size, and of 

 a form calculated to resist pressure, — such as Tur- 

 ritella communis, Trophon clathratus, and Mangelia 

 turricula. Fiisus antiquus and Buccinum undatum 

 are generally represented only by worn fragments 

 of the Columella, and Cyprina idandica is always 

 found in fragments. The author thought that the 

 association of the various species distributed with- 

 out order through the clays shows that they could 

 not have lived together on the same bottom, but 

 that they must have been to a great extent trans- 

 ported. He contended that the admixture of shells 

 in the Boulder-clay was due to the tendency of the 

 sea to throw up its contents on the beach; whence 

 changing currents and floating ice might again re- 

 move them, and to the oscillations of the land 

 bringing all the beds at one time or another within 

 reach of marine erosive action. He maintained 

 that it is in the distribution of land and sea at the 

 period of deposition of the Lancashire deposits, and 

 not in astronomical causes, that we must seek the 

 explanation of the climate of that period, the con- 

 ditions of which he endeavoured to explain by a 

 consideration of the proportions of the species and 

 the natural habitats of the shells found in the 

 drifts. 



Geology of the Redesdale Ironstone Dis- 

 trict. — This is the subject of a valuable paper by 

 G. A. Lebour, T.G.S., reprinted from the Trans- 

 actions of the North of England Institute of Mining 

 and Mechanical Engineers. The author describes 

 the limits and physical features of the district, the 

 stratigraphy, and the ironstone shale, as well as 

 the " faults " traversing the strata. He also gives 

 a detailed account of the various sections passed 

 through at the dijGFerent pits. A contour map of 

 the ironstone district at Bedesdale accompanies 

 the paper, which is throughout of an important 

 character. 



Mud-Craters on the Persian Coast.— At 

 the fest meeting of the Geological Society, Lieut. 

 Stiffe read a paper on this subject. He stated that 

 the coast of Mekran, extending from near the 

 western frontier of India to the mouth of the 

 Persian Gulf, was stated by the author to be a 

 nearly rainless district, consisting of clay plains 

 with precipitous tabular hills, the former veined 

 here and there withcrystalline gypsum, the latter 



composed of clay capped and sometimes interstrati- 

 ficd with coarse, friable, fossilif'erous calcareous 

 strata, from five to thirty feet thick, supposed to be 

 of Miocene age, and all horizontal, or nearly so, 

 except at the extreme east and west, where the 

 strata are inclined at an angle of from 40° to G0°. 

 Along the coast there are no distinct traces of 

 volcanic action, but on the north coast of the 

 Persian Gulf a similar formation has been much 

 disturbed by the protrusion of recent volcanic 

 material ; near Jashak to the west there is a hot 

 mineral spring, and near Karachi there are springs 

 of pure hot water. The author described the mode 

 in which denudation is effected in this region by 

 occasional heavy rains, and by the constant action 

 of the sea upon the coast, and then noticed the 

 occurrence, within a few miles of the shore, of 

 numerous peculiar mud-craters, forming hills varying 

 in height from 20 to 300 or 400 feet above the 

 plain, of a regular conical form, with truncated tops, 

 and the sides sloping at an angle of about 40\ The 

 summits of these hills present a circular cup with 

 a narrow border, Clled with semifluid mud, which 

 occasionally flows slowly over the margin of the 

 crater. The author considered that the conical 

 hills have been formed solely by these overflows. 

 He believed that a small shoal occurring off the 

 coast near Jashak might be produced by one of these 

 craters, and was inclined to ascribe tlieir existence 

 to hydrostatic pressure rather than to volcanic 

 action, especially as by the concurrent testimony of 

 several natives the discharge from the craters is 

 greater during spring-tides. The thickness of the 

 clay forming the plain is probably very considerable ; 

 it extends for some miles from the shore, sinking 

 gradually to 20 or 30 fathoms, when there is a 

 sudden and often precipitous descent to a depth of 

 300 or 400 fathoms. The author suggested that, 

 since the deposition of the Miocene beds, the great 

 submarine cliff may have been raised above the sea ; 

 that the land was then depressed to near its present 

 level, causing the removal of the beds to tlie pre- 

 sent coast-line, and that a further depression fol- 

 lowed by upheaval gave origin to the inland cliffs. 

 Evidence of the last depression is furnished by the 

 presence of borings of lithodomous mollusca in the 

 clifts considerably above the present sea-level. 



NOTES AND QUERIES. 



Pollen-grain. — In the botanical column of the 

 October number, "R. H. N. B."asks as to the pro- 

 bal)le plant from which a pollen-grain is derived 

 of which he gives a figure, numbered 147. It 

 appears to me that it maybe a representa'iou of the 

 pollen of Passiflora carulea, of which a good figure 

 is given in " The Microscope," by Dr. Carpenter, 

 figure 189; but that the figure is not peifectly 

 delineated by your correspondent, or may h;ive been 

 examined by an inferior lens, or possiiily not illu- 

 minated to the best advantage.— 6'. M. Major. 



