&32 Transactions. — Geology. 



Scaphula (?) lanceolata. 



Right valve. Shell small, thin, compressed, smooth, much elongated, 

 not carinated behind, very inequilateral. Anterior portion short, rounded. 

 Posterior portion elongated, gradually tapering, truncated at the end. 

 Posterior dorsal margin straight. Hinge line straight posteriorly, curved 

 anteriorly, edentulous in the centre. Eight anterior and eleven posterior 

 teeth all nearly parallel to the hinge line. The three or four most anterior 

 teeth are short, all the rest are elongated. From the umbo a narrow con- 

 cave cartilage pit slopes very obliquely backwards, and divides the two sets 

 of teeth. 



Length, *7 inch ; height, "25 inch. 



Locality. Petane. Collected by Mr. A. Hamilton. 



Probably a new genus, as the shape is very different from the Indian 

 shells and the posterior teeth are not branched. 



Mytilus striata s. 



Shell elongated, inflated anteriorly, compressed posteriorly ; finely 

 radiately ridged and crossed by concentric rugose growth-marks. Umbo 

 acute, terminal, compressed, strongly curved ventrally. Ventral margin 

 slightly undulating ; dorsal margin rapidly rising from the umbo to about a 

 third of the length, then parallel to the ventral margin ; posterior end 

 truncated. 



Length, 1-15 inch ; height, *52 inch. 



Locality. Broken Eiver. 



Art. XLL — On the Geological Structure of the Southern Alps of New 

 Zealand, in the Provincial Districts of Canterbury and Westland. By 

 Professor Julius von Haast, C.M.G., Ph.D., F.B.S. 

 [Read before the Philosophical Institute of Canterbury, 21th November, 1884.] 

 The publication of a new geological map of New Zealand accompanied by 

 sections, issued by the Geological Survey Department, induces me to offer 

 the following remarks on the geological structure of the Southern Alps, 

 which I consider in some of its most essential features to have been alto- 

 gether misunderstood by the officers of that survey. 



In my former publications I stated that the Southern Alps are only the 

 eastern wing of a huge anticlinal arrangement, of which the western portion 

 has been either destroyed or submerged below the Pacific Ocean. It thus 

 exhibits the same one-sided features so conspicuous in almost every alpine 

 chain of which the geological structure is known. 



