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argillaceous strata, the distribution of which, and, as a rule, also themineral character, indicate that they were related to a closely-adjacent■shore-line, as they often pass almost suddenly from coarse conglo-merates into narrow strips of fine mud and clay, such as are depositedin the centres of deep channels and inlets.

The New Zealand seas have yielded about 450 species, of existingshells, of which 120 have been found in this formation, together with25 forms which are now extinct.

They are specially characterized by the occurrence of Ostrea ingens,Murex octagonus. Fusus triton, Struthiolaria cingulata, CMone assimilis,Chama huttoni, and Pecten gemmulatus.

Pig. 7.

1. Pecten vellicatus. 2,3. Ostrea ingens (Te Aute). 4. Murex zealandica. 5. Arach-noides zelandi®. 6. Struthiolaria sulcata. 7. Chama huttoni. 8. Terebratellacruenta.

In Otago the beds are partly marine, partly lacustrine, with lig-nite deposits at their base. The marine beds are exemplified atMataura Falls and in the vicinity of Landslip Hill, Pomahaka Valley;the lacustrine beds by deposits containing fossil fish at Bannockburnand St. Bathan’s, Central Otago.