McLeod. — Note on the Cave at Papatu. 343 



— a skeleton of magnetite outlines the original form and 

 cleavage-cracks. The magnetite always shows alteration to 

 haematite. A little enstatite is present in each slide. 



There may be a little augite present, but it could not be 

 distinctly identified, as the ferro-magnesian minerals are more 

 or less altered into serpentinous matter. 



Hornblende, much altered, occurs sparingly in well-de- 

 veloped crystals, showing the characteristic prismatic cleav- 

 age. In each slide there are several long prismatic and 

 lozenge-shaped bodies, rendered almost opaque with magne- 

 tite dust. They may originally have been hornblende. In 

 one slide a plate of one of the dark bodies, besides the mag- 

 netite dust which renders it almost opaque, contains enclo- 

 sures of large grains of magnetite and a small idiomorphic 

 crystal of plagioclase feldspar, and, embayed on the edge, a 

 small grain of quartz. 



Quartz occurs as hexagonal plates and interstitial. The 

 former are rare and may be a primary generation. 



There is much calcite present in the rock, and a little 

 carbonate of iron and magnesia. 



From the crosscut at the 300 ft. level, at a point imme- 

 diately below No. 5 shaft, occurred a few small kernels of 

 black greenish-grey rock enclosed in the decomposed ande- 

 site. Microscopic examination proved it to be the same 

 rock as that just described from the south-east crosscut 

 from No. 1 shaft, some 1,000 ft. distant, but more altered, 

 with the result that calcite, haematite, and quartz are more 

 abundant. 



Art. XLII. — Note on the Cave at Papatu, Ormondville, 



Hazvke's Bay. 



By H. N. McLeod. 



[Read before the Wellington Philosophical Society, 38th August, 1900.'] 



This cave is situated about a mile and a half from the railway- 

 station at Ormondville, in the southern part of Hawke's Bay. 

 While it is not a very large cave, it has several interesting 

 points about it, and is worth a visit in passing. 



There are two portions to the cave, which may be likened 

 in shape to an ordinary iron pot, the handle representing a 

 passage which opens out into a small blind gully, and the 

 body of the pot representing the main cave. 



To reach the main entrance it is necessary to ford the 

 Manawatu Eiver, a matter which is easy enough at this spot 

 in ordinary times. The floor is almost on a level with the 



