Nephrite and Mag neslan Hocks of New Zealand. 207 



Hitchin and Bedford Lave also been included for comparison. 

 Rocks of Scandinavian origin, and especially those of the Christiania 

 province, are abundant throughout the whole area : such well- 

 known types as rhomb-porphyry and nordmarkite are common. 

 Kocks from the Cheviots and Central Scotland are more abundant 

 than was formerly believed, and specimens have also heen identified 

 from the Old Red Sandstone conglomerates of Forfarshire and from 

 Buchan Ness (Aberdeenshire). Lake-District rocks probably also 

 occur in small quantity. Much of the Chalk and flints appear 

 to be of northern origin. It is concluded that an older Boulder- 

 €lay, containing foreign erratics, the equivalent of the Cromer 

 Till, once extended over the whole district, but was subsequently 

 incorporated with the Great Chalky Boulder-Clay. The Scan- 

 dinavian ice advanced from the direction of the AVash, bringing 

 with it Red Chalk and bored Gryphaeas from the bed of the 

 North Sea, and carding them as far west as Bedford. Rocks 

 from the north of the British Isles become progressively scarcer 

 from west to east, and the distinctive types are absent to the 

 east of Cambridge. They appear to have been brought by 

 an ice-stream coming from a northerly direction, which probably 

 to a certain extent replaced the Scandinavian ice towards the 

 east. 



2. ' The Nephrite and Magnesian Rocks of the South Island of 

 New Zealand.' By Alexander Moncrieff Finlayson, M.Sc. 



The magnesian rocks described in this paper are a disconnected 

 series of intrusive peridotitcs, forming a more or less defined 

 belt along the western portion of the South Island, parallel 

 to the trend of the island and to the structural and geographic 

 axes of the main Alpine range. The course taken by these 

 rocks apparently follows one of the main Pacific trend-lines, 

 the nature of which will be more fully understood with the 

 further elucidation of the structural geology of t lie region. The 

 rocks are intrusive into sedimentary strata of ages varying from 

 Ordovician to Jura-Trias; and, as far as can yet be determined, 

 all the exposures appear to be of approximately contemporaneous 

 origin. 



One of the most interesting groups is at the Dun Mountain, 

 Nelson, where the original dunite of Hochstetter occurs, associated 

 with magmatic segregations of chromile, bands of pyroxenite, 

 serpentine-rock, and a variety of rock-types of contact-meta- 

 morphic origin bordering on the Triassic limestone which is 

 intruded into by these rocks. The rocks of the contact-zone 

 include grossularite-diallage rock, serpentine-amphibole rock, and 

 epidote-rock. 



In Westland, near Hokitika, the rocks occur as a series of sills 

 which are of two varieties — massive or foliated serpentine-rock 

 and serpentine-talc-carbonate rock. The former are often seen to 



