Field. — Tivo New Ferns. 495 



his own satisfaction that the rounded form is due to the inclu- 

 sion of waterworn fragments from deep-seated conglomerates. 

 In the present case there is no evidence to show that such has 

 happened. The rounding and polishing is so fine that it can 

 only have been caused by friction, and the only suggestion that 

 has occurred to me is that which Dr. Bonney rejects in the 

 Kimberley case — viz., that the fragments have been rolled up 

 and down in the crater. This point, however, has no bearing 

 on the probability of the occurrence of diamonds. 



In conclusion, from the similarity of the Kakanui breccia 

 to that of Kimberley, it would excite no surprise if they were 

 discovered, but it could hardly be predicted that diamonds 

 occur at Kakanui. 



Bibliography. 



The following papers refer, en passant, to the neighbourhood 

 of Kakanui : — 



1850. Mantell " On the Geology of New Zealand," Quart. 

 Journ. Geol. Sci. (1850), vi, p. 324. 



1870. Charles Traill, " On the Tertiary Series of Oamaru 

 and Moeraki," Trans. N.Z. Inst., vol. ii, p. 166. 



1877. " Oamaru and Waitaki Districts," Progress Reports, 

 Geol. Surv. of N.Z., p. 41. 



1883. " The North-eastern District of Otago," Progress 

 Reports, Geol. Surv. of N.Z., p. 63. 



1886. Hutton, " On the Geology of the Country between 

 Oamaru and Moeraki," Trans. N.Z. Inst., vol. xix, pp. 415-30. 



On diamonds : Carvill-Lewis, Geol. Mag., 1887, p. 22. Bon- 

 ney and Miss Raisin, Geol. Mag., 1891, p. 413. Bonney, Geol. 

 Mag., 1899, p. 309 ; Proc. Roy. Soc, 1900, lxvii, p. 475 ; Geol. 

 Mag., 1900, p. 246. 



Art. LIV. — Tivo New Ferns. 

 By H. C. Field. 



[Read before the Wellington Philosophical Society, 5th April, 1905.] 



In December, 1903, one of my sons, who had been visiting 

 Auckland, brought me some plants of ferns which are either 

 wanting or extremely rare in this part of the colony, and I 

 potted them at once. Among them was one which appeared 

 strange to me, and which my son said he had found in some 

 scrub near Takapuna Lake. It was a male plant with only 

 barren fronds about 2 in. long, and which looked like those 



