NO. 2.] JURASSIC SEDIMENTARY ROCKS. 47 



No. 4. Hard dark-gray, finely-grained, sandy marl, with small, 

 irregular accumulations of pyrite. The stone is much broken and traversed 

 by veins of calcite. Some pieces contain small portions of pale-gray, very 

 soft marl (no. 4 a), which was also found unconnected with the hard marl. 

 The sandy hard marl is very rich in shells of lamellibranchs, which, how- 

 ever, are partly very much broken and crushed, partly preserved only in 

 indeterminable sections. In addition to these, there are inarticulate brachio- 

 pods and belemnites. These brachiopods and belemnites, and some frag- 

 ments of indeterminable lamellibranchs, are also included in the pale-gray, 

 soft marl, (no. 4 a) occurring together with the sandy, hard, dark-gray marl, 

 and found loose in isolated pieces. 



Both the pieces of sandy, dark-gray, hard marl, and those of soft marl 

 found loose, were collected on August 2nd 1896. They were found at a 

 height of about 2333 feet (710 m.) above sea-level, 300 m. NW. from 

 Elmwood; cf. p. 11, No. 1 a, "lowest horizon". Judging from the state of 

 preservation of the generally rather large blocks of sandy, dark-gray, hard 

 marl, they have most probably been found in situ. 



No- 5. Yellow or gray and greenish hard calcareous, to some extent 

 sandy marl (" Steinmergel"). 



Most of the pieces, which were found loose, show a soft, brown or rusty 

 red weathered crust. Some pieces of the rock are quite compact, uncommonly 

 hard, with a conchoidal fracture; the fractured surface is glossy black and 

 of a greasy appearance. Other pieces are of coarser grain; but upon the 

 whole, they are always quite finely grained, with an earthy fracture. By 



* 



containing more sand and being less calcareous, this rock gradually passes 

 over into clay sandstone (No. 6). 



The rocks contain numerous impressions and fragments of ammonites 

 (with nacreous shells) and indeterminable remains of belemnites; and, very 

 rarely, remains of lammellibranchs are found. Besides indications of plant- 

 remains, one of the pieces contains traces of a coal-like substance. 



These pieces were found loose on the talus, on July 10th 1896, at a 

 height of 100 feet (30 m.) above sea-level, behind Elmwood, cf. pag. 16, and 

 on July 14th 1896, at a height of about 370450 feet (113137 m.), at the 

 south-western end of Windy Gully, cf. p. 13. 



