192 Transactions. 
identify the species is by means of the muscular scars. This again is an 
extremely variable charaeter, but the variations do not conceal the fact 
that there are two quite distinct forms. The left valve of Anomia has - 
three muscular scars on the central disc; the uppermost, and the anterior 
or middle one, are byssal adductors, while the lowest or posterior is the 
adductor of the valves. 
In the young A. undata the arrangement of these scars is much the same 
as that of A. trigonopsis—i.e., triangular, the uppermost being much larger 
than either of the others. In the adult A. undata the three impressions - Ч 
are arranged almost іп а vertical line, and are crowded together. 
An Ж 
elongated A. trigonopsis, such as the neotype figured by Suter (1915), 3 
often shows a somewhat similar arrangement, but the lower byssal adductor 
gi 
ANT. 
is still paired with the valve-adductor, and both are separated from the — 4 
upper byssal adductor (see Plate 16, fig. 10). In fully-grown A. undata the 
valve-adductor is generally the largest; this is never so in the other species, — 
uter’s identifications, being based on the undulations, are unreliable; — | 
indeed, the true A. wndata was generally classed by him as A. huttom, 
which according to his usage comprised the smooth, circular shells. е 
The species does not appear to have existed in the Miocene; it is 
particularly common in the Petane clays at Maraekakaho, also at Nuku- 
maru, while there is a Recent example in the Dominion Museum from an 
unknown locality. 
Lima mestayerae n.sp. (Plate 16, figs. 11, 12.) 
Height, 16 mm. ; length, 14 mm. 
Locality.—1096, clays below limestone, Esk Bridge, Petane. 
Remarks.—Distinguished from L. lima by small size and greater number 
of ribs, 22 instead of 18. Compared with a young L. lima of the same 8120, 
the ears of L. mestayerae are much smaller, the shell is narrower and conse- 
quently the ribs also, while the ligamental area is a great deal higher.. I am 
indebted to Miss Mestayer for the loan of Recent material for comparison. 
Venericardia (Pleuromeris) marshalli n. sp. (Plate 16, figs. 1, 2.) 
1906. Venericardia corbis Philippi: Suter, Trans. N.Z. Inst, vol. 38, p. 317 
not o ilippi 
1913. Venericardia corbis 
not of Philippi 
T Philippi: Suter, Man. N.Z. Moll., p. 908, pl. 53, fig. 3 
ppi). 
1915. Venericardia unidentata (Basterot): Iredale, Trans. N.Z. Inst, vol. 47, 
р. 487 
W 
(not of Basterot). 
The identification of this New Zealand shell with V. corbis, a Pliocene 
and Recent species of the Mediterranean, was made by Dr. W. H. Dall, 
and was accepted by Suter (1906, p. 318). Such a distribution is in itself 
suspicious ; and as, by good fortune, the Dominion Museum has a copy 9 
Philippi's Enwneratio Molluscorum Siciliae, in which V. corbis is described, 
& 
Er. 
T 
se 
1 
