402 PHOCEEDIXGS OF THE GEOLOGICAL SOCIETY. [JunC 5, 



Mr. SoLLAS had examined sections of the fossils from the Cam- 

 bridge beds under the microscope, but had failed to find the canals 

 or tuberculated spicules characteristic of Alcyonaria. He had, 

 however, in the sand found numerous indisputable sponge- spicules. 

 He had, moreover, found in sections of the coprolites spicules such 

 as were regarded by Dr. Bowerbanb as characteristic of sponges. 

 He hoped, however, to recur to the subject. Both Mr, Fisher and 

 himself concurred in removing these nodules from the category of 

 concretions, and placing them under the head of organic fossils. 

 The transported blocks in the beds bear evidence of glacial action, 

 and, he considered, had been brought from Scotland or Scandinavia. 

 The cold sea then existing at the base of the Scandinavian chain of 

 mountains flowed southward over the bottom of the ocean, carrying 

 with it mineral matter in solution, particularly phosphates ; so that 

 in this way, he thought, some portion of the phosphatic matter was 

 derived from the decomposition of the volcanic rocks north of the 

 Lammermuirs, which were rich in this substance, and of which rocks 

 he had found fragments near Cambridge. He considered that, under 

 certain circumstances, the phosphatic matter present in water would 

 combine with animal matter, and hoped at some future time to offer 

 some remarks on this subject to the Society. 



June 5, 1872. 



Isaac Shone, Esq., of Bersham Hall, near Wrexham, Denbighshire, 

 was elected a Fellow, and Prof. J. D. Whitney, of Cambridge, U.S., 

 a Foreign Correspondent of the Society. 



The following communications were read : — 



1. Notes on Sakd-Pits, Mtjd-dtschaeges, and Brine-Pits met with 

 during the Yakkand Expedition of 1870. By Geoege Hendeeson, 

 M.D., F.L.S., Surgeon H.M. Bengal Medical Service, and lately 

 Medical Officer to the Yarkand Expedition of 1870. 



(Communicated by E. Etheridge, Esq.) 



Whilst accompanying Mr. T. D. Forsyth to Yarkand in the summer 

 of 1870, we came upon extensive tracts of ground indented with 

 very remarkable circular pits, which I was very much puzzled to 

 account for. 



Where first seen, they appeared like the holes made in washing 

 for gold, as practised both in Tibet and Yarkand ; but there was 

 none of the excavated material to be seen round their margins, and 

 they were a hundred miles or more from any human habitation ; 

 besides, they were much too regular in size and shape to be thus 

 accounted for. 



I noted at the time every circumstance which I thought likely to 

 give a clue to the manner of their formation ; but, from the rapidity 



