AJfNIVERSAEY ADDKESS OF THE PKESIDENT. CV 



niences with a detailed account of a peculiar and local series of 

 Marl-beds on the left bank of the Eeuss, near its junction with the 

 Aare, to which the local name of 8chambelen or Tschembelen has 

 been given. It rests immediately on the Keuper dolomite, and 

 is overlain by Grryph sea-limestone full of Ammonites, Selemnites, 

 and GryphcEa ( G. obliqua) ; its total thicliuess is about 35 feet, but 

 it consists of twenty-one different beds, and, as Prof. Heer states, 

 it forms a most important document respecting the organic nature 

 of the country, and tells a wonderful episode in the earth's history. 



After carefully describing the difierent fossil contents of each 

 bed, in order to give a specimen of the manner in which the rocks 

 of this country were gradually formed, and to show how their 

 fossils tell their history, he states that the upper and lower marls, 

 forming about 15 feet of the whole, are absolutely unfossiliferous ; 

 the six loAA'est beds are purely marine ; land-insects appear in the 

 seventh and ninth, but are most numerous in the eleventh ; they 

 then gradually diminish upwards, and are no more seen after the 

 eighteenth, which, like the seventh, contains marine animals v/hich 

 had almost entirely disappeared since the deposition of the tenthbed. 



From all these facts Dr. Heer concludes that these strata must 

 have been deposited in a quiet arm of the sea, protected by a reef 

 of rocks, or a long promontory, from the disturbing action of the 

 waves. Thus only can we account for the excellent preservation 

 of the remains of organic life which were quietly covered up by the 

 deposit of silt. That dry land existed close by is proved by the 

 abundance of land-insects, which are so Avell preserved that they 

 could not have been drifted from a distance. They must also have 

 been rapidly covered up, consequently the water which washed 

 them down, probably a river, must have held much earthy matter 

 in suspension. The commencement of these insect-remains in the 

 seventh bed, and the total disappearance of marine life in the 

 eleventh, combined with the fact of its reappearance in the thir- 

 teenth, shows that the earth was at first gradually rising, until at 

 the time of the deposition of the eleventh bed the salt water was 

 entirely excluded. At this period a change took place, the ground 

 again began to sink, the sea burst in, the insect-remains become 

 scarcer and scarcer, and the marine shells and other forms of life 

 rapidly reappeared in the reversed order to that in which they had 

 disappeared, and at last we find the same unfossiliferous marls. 

 By the continued sinking of the ground, the mainland retired 

 to such a distance that its productions no longer reached this 

 spot ; and at length the depth became so great that the condi- 

 tions of life were no longer suitable to the existence of marine 

 animals. The author concludes witli a comjiarison of the marine 

 portion of this series of beds with his observations on an analogous 

 protected Grulf on the coast of Madeira which he had often visited. 



Comparing the insect-forms of the Schambelen with those of the 

 Lias in England, ^^^irticularly between Charmouth and Lyme 

 Regis, he shows that the sketch of organic life which he has here 

 given is not purely local, but that it represents the natural state 



