Park. — The Loioer Mesozoic Rocks of Neio Zealand. 389 



Eiiomjihalus, all Palaeozoic genera, which led him to place his 

 Mount Toi'lesse formation, of which these beds formed a part, 

 in the Carboniferous period.-'- These genera have never been 

 identified in other collections made at Kocky Gully, and we 

 can only conclude that the forms to which these names were 

 applied belonged to other genera. 



The Eocky Gully marine beds are about 2,000 ft. higher in 

 the series than the plant beds, being separated from the latter 

 by the sandstones, shales, and claystones just described. The 

 conformable relations of the Eocky Gully Spiriferina beds to 

 Tank Gully plant beds seems to admit of little doubt, and is a 

 point upon which Sir Julius von Haast and Mr. McKay were 

 both agreed. 



The fossils occur in indurated claystones and sandstones, 

 which are interbedded with a pebbly bone bed varying from 

 2ft. to 4ft. thick. The bone bed contains a large number of 

 broken shells and rolled fragments of bone. The sandstones, 

 on each side of the bone bed, contain a few fossils, mostly 

 Brachiopoda, scattered through a thickness of sevei-al feet. 



A more varied assemblage of marine shells occurs in a bed 

 of black claystone underlying the sandstone zone. This clay- 

 stone has been subjected to great lateral thrust, with the 

 result that the contained fossils are often flattened and dis- 

 torted ; while the stress has induced in the rock itself a 

 tendency to break on exposed surfaces into long prisraoidal 

 pencils, an effect which adds considerably to the difficulty of 

 securing perfect unbroken shells. In places the fossiliferous 

 sandstones and claystones are slightly calcareous. 



I collected from the lower horizon Halohia{7), Mega- 

 ■lodon(?), Nuculaiia, Athyris, Bhynchonella, and Spiriferina, 

 three sp. ; and from the upper or bone-bed horizon Ortho- 

 ceras, Pleurotoviaria, Ttirbo, Pentacrinus, several bivalves not 

 determined, and some fragments of saurian bones. Two small 

 vertebrae were noted, but not collected, in a cavity in a large 

 boulder. They were exposed in elevation so as to show the 

 full size of the disc, which in the case of one was f in. in 

 diameter, and of the other ^^g- in. less. They were flat or 

 nearly so. 



From Eocky Gully the section was followed up the Clyde 

 Valley to the foot of Mount Goethe, on the main alpine divide, 

 a distance of nine miles as the crow flies. 



The rocks consist of a great succession of sandstones, 

 greywacke, shales, and claystones. The sandstones are pale- 

 grey, greenish-gi-ey, and yellowish-green in colour, and vary 

 in texture from fine-grained to coarse, gritty, and pebbly, 

 in places passing into conglomerate. They are siliceous, and 



* Reps. Geol. Expl., 1872-73, p. 6. 



