122 Transaction*. 



Conclusion. 



I must here express my indebtedness to Messrs. W. and G. 

 Donaldson, of Macrae's, and Messrs. George Reid and Robert 

 Lee, jun., of Glenorcby, for the many facilities and liberties 

 they allowed me during my examination of the mines. To 

 Dr. P. Marshall and Mr. D. B. Waters, of the Otago School of 

 Mines, my warmest thanks are due for much valuable advice 

 in the laboratory and in the preparation of this paper. 



EXPLANATION OF PLATE XVI. 



a. Section of scheelite, showing cleavage, and quartz (white), x 36 dia- 

 meters. 

 6. Scheelite, clouded, with quartz stringers, x 36 diameters. 



c. Illustrates metasomatic replacement. Dark fragments of scheelite, 



with calcite in the centre of the photograph, x 36 diameters. 



d. Scheelite (dark), separated from gangue (white) by strings of pyrite 



(black). The specimen was taken from Glenorchy. x 3 diameters. 



Art. XI. — Some Alkaline and Nepheline Rocks from WesUand. 



By J. P. Smith. 

 Communicated by Dr. Marshall. 



[Read before the Otago Institute, 12th November, 1907.] 

 Plates XYII-XIX. 



The rocks about to be described were obtained from the gravels 

 of the watershed of the New River and its tributaries. They 

 embrace a series of hypabyssal rocks ranging from acid granite 

 porphyries to basic lamprophyres and gabbro diabases. Very 

 few of the examples have been found in situ, but there is every 

 reason to believe that the whole of the series were set free by 

 erosion from the northern slopes of the Hohuna Range and 

 from the adjoining Te Kinga Mountain. The humidity of the 

 climate and a heavy rainfall has clothed the hillsides of Westland 

 with a dense forest growth and a depth of humus matted with 

 roots which effectually conceals the rock-surfaces. It is only 

 above the bush-line, or upon the precipitous side of some deeply 

 incised creek, or in some artificial cutting, that exposures of 

 the underlying rocks occur. These limited exposures afford 

 sufficient evidence to permit the rocks of the different forma- 

 tions to be classified and the areas of the formations to be 

 defined. They, however, give few opportunities to examine or 

 locate any dykes which may traverse these formations. It is. 



