179 



NOTES ON NEW ZEALAND PELECYPODS. 

 By W. R. B. Oliver, F.L.S. 



Read 12th. January, 1923. 



The appearance of Suter's work on the Mollusca of New Zealand, in 

 1913 made a great advance in the study of the subject by making 

 readily available descriptions, references to literature, figures, and 

 other information on all the species admitted by him. The work 

 forms a new starting-point for making known the constitution and 

 relationships of molluscan fauna of New Zealand. Iredale, in an 

 article published in vol. xlvii of the Transactions of the New 

 Zealand Institute, next took up the subject from the point of view 

 of nomenclature, made a number of changes in names, and proposed 

 various new arrangements in the generic locations, of the species. 

 In the same volume I removed thirty- two names from the records 

 of species from the Kermadec Islands in Suter's book. Other work 

 on the recent species of New Zealand Mollusca since the appearance of 

 Suter's Manual consists mainly in additions to the fauna made by 

 E. A. Smith (Eeport, " Terra Nova " Expedition) and Miss M. K. 

 Mestayer (Trans. New Zealand Inst., vols, xlviii, 1, li). 



A critical examination of types in the Dominion Museum and other 

 material does not entirely confirm the results of either Suter or 

 Iredale. Suter worked with plenty of New Zealand specimens, 

 but appears not to have troubled to compare exotic species. Iredale, 

 on the contrary, has ample foreign material to study, but, judging 

 by his results, did not have sufficient New Zealand specimens, so 

 that many of Suter's mistakes are repeated in Iredale's lists. The 

 specimens available to me are not adequate either in New Zealand 

 or exotic species, yet I have little doubt that many of the species 

 of Pelecypods admitted by Suter and not here dealt with, will, when 

 proper comparisons are made, share the fate of some of those I have 

 examined. Unfortunately, Suter did not purge the New Zealand 

 list of all the exotic species included by Hutton, and this result is 

 especially misleading when new names founded on foreign material 

 are included by Suter as good New Zealand species. 



1. Anomia walteri. Hector. 



The typical form of this species I have found only under stones 

 near low-tide mark at the Bay of Islands, and on rocks between 

 tide-marks in sheltered water at Port Fitzroy, Great Barrier Island, 

 attached to a shell of Mytilus canaliculus. The shell is of regular 

 shape, broader than high, with radiating ribs and the valves thin 

 and almost transparent at the edges. This form is well figured by 

 Suter (Man. N.Z. Moll., pi. Ivii, fig. 10). Living on exposed rocks 

 at the Bay of Islands, however, it becomes irregular in outline, the 

 valves are much thicker, frequently the radial ribs are obscure or 



