Yol. 52.] GLOBIGERINA-LIMESTONES OF MALTA. 461 



23. Notes concerning certain Linear Marks in a Sedimentary Rock. 



By Prof. J. E. Talmage, D.Sc, F.G.S. (Read March 11th, 



1896.) 



[Abstract.] 



The marks described in the paper occur in a fine-grained argil- 

 laceous sandstone referred by the U.S. Geological Survey to the 

 Triassic or Jura-Trias period, which is found on a low tableland 

 within 2 miles of the bluff's overlooking Glen Canyon. The marks 

 commonly appear as straight lines intersecting at right angles, but 

 some have a pinnate distribution, suggesting engravings of frost- 

 flowers. A description of the markings is given, and various 

 experiments made in the laboratory to illustrate the effects of 

 formation of crystals formed over sediment are described. (See a 

 paper by the same Author in the Utah University Quarterly for 

 December 1895.) 



24. The GrpsuM Deposits of Nottinghamshire and Derbyshire. 

 By A. T. Metcalfe, Esq., E.G.S. (Read January 8th, 1896.) 



[Abstract.] 



The gypsum deposits of these counties occur in the Upper Marls 

 of the Keuper division of the Triassic system. The author describes 

 their occurrence in thick nodular irregular beds, large spheroidal 

 masses, and lenticular intercalations, and their association with satin- 

 spar, alabaster, selenite, and anhydrite. 



25. Contributions to the Stratigraphz and Paleontology of the 

 Globigerina-limestones of the Maltese Islands. By J. H. 

 Cooke, Esq., E.L.S., E.G.S. (Read April 15th, 1896.) 



[Abstract.] 



A bibliography of the GZofo'^mna-limestones is followed by some 

 remarks on the physical features and general distribution of the 

 strata. The limestones are divided into nine subdivisions, lettered A 

 to I, the former being uppermost. Four seams of phosphatic nodules 

 form the subdivisions B, D, G, and I, and local nodule-bands also 

 occur in E. The subdivision G serves as a line of demarcation 

 between the Langhian Series (Miocene) and the Aquitanian 

 (Oligocene). Details of the lithological and palseontological cha- 

 racters of the various subdivisions are given, and the Author 

 concludes that I and the lower part of H were laid down on a 

 sinking sea-floor, in about 300 fathoms of water ; that the upper 



