Notices of Memoirs — Royal Society of Tasmania. 463 



within my personal knowledge that makes additional difficulty 

 in accounting for the formation of ground-ice. The main pipe 

 that supplies the pumping engine of the Detroit Waterworks 

 is two feet in diameter, and is 20 feet under the surface of 

 the river, at the distance of 100 feet from the shore. In the 

 winter of 1868 ground-ice adhered to the wire covering over the 

 mouth of the pipe, placed to prevent the entrance of fish into 

 the pipe. The whole wire was so covered with ice as to prevent the 

 action of the pumps by impeding the entrance of water. It is very 

 difficult to account for the ice at that depth, while the water flowed 

 freely above and below the pipe. The cold could not be transmitted 

 from the shore along the iron pipe, for the pipe was not covered 

 with ice. It seems that the condition of rapid flow through narrow 

 or constricted places, like the interstices between stones, or the wire- 

 guard, are necessary to produce congelation ; but why it should be 

 produced in such difficult circumstances I am not able to say. The 

 Corporation of Detroit had the matter considered by those they 

 thought competent to give an opinion, without any result, but that 

 of having men to break the ice off the. pipe-mouth daily, or when- 

 ever the temperature was low. The circumstances of this pipe are 

 more difficult to account for than the ordinary ground-ice at the 

 more moderate depths, because 20 feet of clear water and 100 feet 

 from the shore are the difficult parts of the problem." 



Here, then, is a riddle for some of our physicists to solve ; for it 

 must be admitted that the mode of formation of ground-ice is still, 

 to say the least, imperfectly understood. — J.Gr. 



n^OTiciES oip nvcEnvLOii^s. 



I. — Monthly Notices of Papers and Proceedings of the Eotal 

 Society of Tasmania for March, April, and May, 1875. 8vo. 

 pp. 29 and viii. (Hobart Town.) 



ONLY one paper calls for attention on our part, viz. that by the 

 Eev. J. E. Tenison Woods, " On some Tertiary Fossils from 

 Table Cape" (pp. 13-26). The beds from which the fossils were 

 obtained are correlated with portions of two horizons in the Cape 

 Otway Series, Victoria — an Upper or Polyzoal Limestone, with 

 Hemijpatagus Forbesii, Woods and Duncan, and Cellepora Gamhier- 

 ensis, Busk ; and a Lower, or Brown Clays and Sandstones, dis- 

 tinguished by the presence of Pecten laticostatus, Quoy. From the 

 Tasmanian representatives of these beds, twenty-seven species of 

 Mollusca are enumerated, of which eleven are new to science. The 

 Polyzoa are not numerous, being chiefly the remains of the charac- 

 teristic Cellepora Gambierensis, Busk. The Echinodermata are 

 confined to the almost equally characteristic Semipatagus Forbesii ; 

 whilst of the Corals three of the forms belong to already -described 

 species, and two others are probably new. Four species of Forami- 

 nifera are mentioned. The presence of a portion of the great South 

 Australian Tertiary formation leads Mr. Woods to the conclusion 

 that Tasmania has shared in the general upheaval of the south coast 



