300 Transactions. — Zoology. 



The beach is steep, except at the north end, and composed 

 of very coarse quartz sand and broken shells. lb is sheltered 

 from all winds except from the north-east, east, and south- 

 east. 



Excluding the recent alluvia forming the flat around the 

 lagoon, only one rock-formation is represented in this dis- 

 trict — namely, a crumbling grey-coloured granite, which is 

 generally extremely coarse in texture. The feldspars of this 

 granite exist mostly in large tabular crystals commonly from 

 iin. to lin. long, but often reaching a length of 3 in. or more. 

 The quartz is the predominant constituent. It occurs in 

 large grains and irregular aggregates, which become pro- 

 minent on all weathered and water-worn surfaces, thereby 

 imparting a rough and rugged appearance to all the rocky 

 headlands facing the sea. In such a coarse-grained rock the 

 mica occupies a very subordinate place, and in most parts 

 is hardly perceptible to the eye. 



On the coast- line between Totaranui and Anapai going 

 north, and between Totaranui and Awaroa going south, the 

 granite is traversed with veins of grey-coloured crypto-crystal- 

 line quartz, varying from a mere thread to 3 in. or 4 in. in 

 thickness. A mile before the Awaroa Eiver is reached the 

 grey granite is displaced by a wide belt of pink or reddish- 

 coloured granite of intense hardness, and admirably adapted 

 for a building-stone. This belt of pink granite is more than 

 100 yards wide, and in the direction of Awaroa is followed by 

 the grey granite, which thence stretches southward for many 

 miles without interruption. 



This granite is a rock of great antiquity. At Takaka and 

 Biwaka it is seen to be associated with crystalline limestones 

 and quartzites of Lower Silurian age, and the geological con- 

 siderations detailed in my report on the geology of Colling- 

 wood County" afford good reason for the belief that the rocks 

 in this and the surrounding region are the most ancient in 

 New Zealand. 



During a three-months residence at this beautiful place in 

 the summer of 1901-1902 the writer collected 149 different 

 species of Mollusca, including only those whose soft parts are 

 protected with a shell or hard covering. This comparative 

 poverty in molluscous life is doubtless due in part to the 

 extremely coarse and ever-shifting sands, the absence of beach 

 muds and fine sediments, and the exposed position of the 

 enclosing rocky headlands. 



On the other hand, it must not be forgotten that Totaranui 

 is but a small nook in the great gulf contained between Cape 

 Farewell Spit and D'Urville Island, and it is certain that a 



* Geol. Rept. and Explorations, 1888-89. 



