232 



Geological Society i — 







L&pidodendron gasjpianum. 



Leptophlceum rhomhicum. 



Stems and branches... 



Vascular scars 



Leaves 



Long and slender; areoles 

 elongate lanceolate. 



In middle of areole or 

 nearer upper end, accord- 

 ing to the surface exposed. 



Short and much curved 

 outward. 



Small, scaly. 



Unknown ; probably allied 

 to Carboniferous Lepido- 

 dendra. 



Short and stout ; areoles 

 regularly or transverse- 

 ly rhombic. 



Always in middje of 

 areole. 



Long and somewhat 

 straight and erect. 



Long, leafy. 



Known to possess a large 

 Sternbergia-^ith, and 

 to have a very thin 

 cortical layer. 



Fruit 



Structure 





The author further stated that Presl's genus Bergeria is Carboni- 

 ferous and not Devonian, and that it has no special affinity with 

 Leptophlceum or LepidopJiloios ; and he objected to the revival of the 

 name Bergeria. 



March 26th, 1873.— His Grace the Duke of Argyll, K.T., F.K.S., 



President, in the Chair. 



The following communications were read : — 



1. " Synopsis of the younger formations of New Zealand." By 

 Capt. F. W. Hutton, F.G.S., of the Geological Survey of New 

 Zealand. 



In this paper the author gave a summary of the Tertiary and 

 later Secondary formations of New Zealand. He stated that he had 

 been able to determine 375 species of true Mollusca, 12 of Brachio- 

 poda, and 18 of Echinodermata from the Tertiaries ; and under each 

 of the formations which he recognizes he gave the number of species 

 of true Mollusca found in it, indicating the number of recent species 

 and of those belonging to other formations occurring in each. He 

 also noticed the range and distribution of the various formations. 

 The Tertiary groups of strata distinguished by the author are, in de- 

 scending order, as follows: — I. Pleistocene. II. Pliocene: 1, the 

 Newer Pliocene or Whanganui group ; 2, the Older Pliocene or 

 Lignite group. III. Miocene : 3, Upper or Arvatere group ; 4, Lower 

 or Kanieri group. IV. Oligocene : 5, Upper or Hawke's Bay group ; 

 6, Lower or Waitewata group. V. Eocene : 7, Upper or Ototara 

 group ; 8, Lower or Brown-coal group. As belonging to the Me- 

 sozoic series, the author also described beds of Danian age, under 

 the name of the Waipara formation. A species of Belemnitella 

 occurs in beds belonging to the Ototara group, and also in the Wai- 

 para formation. Volcanic action commenced in the North Island 

 during the deposition of the Waitewata group, and has since been 

 almost continuous in the northern, western, and central parts of the 

 island. In the South Island the volcanic formations appear to belong 

 to the later Cretaceous, Oligocene, and Miocene periods. The 

 volcanic rocks of the Chatham Islands belong chiefly to the Upper 

 Oligocene. 



