part 3] THE TEIAS OF ^"EW ZEALAXD. 237 



and more inflated shell, its relatively narrower hinge-line, and 

 much less clearh'-marked folds and sulcus. In its general rounded 

 outline and swollen surface it somewhat recalls full-grown speci- 

 mens of the Alpine Spirigera oxycolpos. 



Hectoeia cu2s'eifoemis, sp. nov. (PL XXY, figs. 4« & 4&.) 



Yalves about equally convex, compressed, and but slightly 

 inflated. The junction of the valves is nearl}'- straight. The 

 hinge-margin slopes very gently away from the beak, and represents 

 the greatest w4dth of the shell. The ventral beak is very small, 

 and projects but slightly above the hinge-margin ; the ventral area 

 is extremely narrow. In front of the hinge-line the lateral margins 

 converge together rather rapidly, and the anterior margin is strongly 

 hollowed out between the ridges. The median sulcus and the 

 rounded ridges on each side of it are well marked in both valves ; 

 they continue in full strength from the beak to the anterior 

 margin. Kidges of growth are rounded and fairh-^ prominent, and 

 the structure of the shell is coarsely fibrous. 



The type-specimen, from Taylor s Creek, is 25 mm. long, 37 mm. 

 wide, and 11 mm. thick. 



Locality and horizon. — A fine specimen in the New Zealand 

 Geological Survey Collection was obtained in the lowest part of 

 the lower Ammonite Bed at Taylor's Creek, in the Hokonui Hills. 

 Prof. P. Marshall lent me a fragment of a valve that he collected 

 at Totara Point, in the harbour of Kawhia. I am at present un- 

 certain about the exact horizon of the Jurassic at Totara Point ; 

 but I think, from an examination of the associated fossils, that it 

 is Bajocian. 



Remarks. — This form is smaller than S. hisulcata, the sulcus 

 and ridges are better marked, and the beaks relatively smaller. 

 It is a dwarfed Jurassic survival of an essentially Upper Triassic 

 group. 



TIL IvELATIOX OF THE NeW ZeALAXD TeTAS TO THAT OF 



jSTew Caledonia axd the Malay Aechipelago. 



New Caledonia lies on the north-westerly continuation of the- 

 Australian festoon or submarine ridge which connects the Auckland 

 Peninsula with Norfolk Island and the Malay region. 



On the south-western side of New Caledonia the Trias shows a 

 close agreement with that -of New Zealand. The points of simi- 

 larity and difference seem to be as follows : — 



(«) At the base occurs a thick detrital series devoid of 

 fossils. Piroutet supposes this to represent probably the- 

 Permian and the lower divisions of the Trias, and it evi- 

 dently corresponds with the Kaihiku Series below the lowest 

 fossiliferous horizon in New Zealand. 



(&) Above this comes a series of shales, greywackes, tuffs, 

 andesitic breccias, and conglomerates, Avhich represent the^ 



