72 Transactions. 



Plate X. 



Fig. 25. Flattened form, plant three years old, lower surface elements ; 



kabikatea. x 192. 

 Fig. 26. Flattened form, plant three years old, upper surface elements; 



kahikatea. x 192. 

 Fig. 27. Bundle, mature kahikatea. x 192. 

 Fig. 28. Rimu ; bundle, cotyledon, x 192. 

 Fig. 29. Transverse outlines — (a) cotyledon ; (b) stage 1 ; (c) stage 2 p 



(d) stage 3 ; (e) shrub; rimu. x 22. 

 Fig. 30. Stage 1 ; rimu ; bundle, x 192. 

 Fig. 31. Stage 2 ; rimu. x 192. 

 Fig. 32. Stage 3 ; rimu. x 192. 

 Fig. 33. Mature leaf ; rimu. x 192. 

 Fig. 34. Transverse outlines, Dacrydium Kirkii — (a, b, c) sections from 



apex to base of mature scale leaf ; (d) large form of leaf ; (e) 



large form, natural sizo ; (/) scale form, natural size, x 12. 



Art. IV. — Some Observations on the Schists of Central Otago, 

 By A. M. Finlayson, M.Sc. 

 Communicated by Dr. P. Marshall. 

 [Read before the Olago Institute, 8th October, 1907.] 

 Plates XI and XII. 



1. Denudation Forms. 



Many of the Central Otago ranges are capped by vast as- 

 semblages of rock hummocks or buttes. These are well dis- 

 played on the Dunstan, Old Man, Carrick, and Rough Ridge 

 Ranges, also at Barewood and Macrae's. As we approach the 

 coast these hummocks become more numerous and smaller, 

 till they finally disappear. They are best seen near mature 

 river development, while sufficient erosion removes them alto- 

 gether. They are thus not enduring features of the landscape, 

 but are brought into existence, and again destroyed, by erosive 

 activity. 



These peculiar forms have been remarked by several observers, 

 notably the late Captain Hutton* and Mr. T. A. Rickardf ; 

 but the only one who discusses their nature is Rickard, who 

 studied them at Barewood. As he observes, they are generally 

 composed of more siliceous and resistant portions of the rock. 

 Basins and cavities are frequently developed near their base, 



* P. W. Hutton, •' Geology of Otago" (Dunedin, L875), p. 91. 

 fT. A. Rickard, " GSoldfielda of Otago," Trans. Am. Inst, Min. Eng., 

 vi 1. xxi, p. 411. 



