NOTES ON A COLLECTION OF TERTIARY LIMESTONES. 
transversely truncated, forming a right angle with the dorsal margin. 
Dorsal line slightly concave. Umbo convex and incurved to the 
ventral side. Dorsal slope with about nine flat longitudinal ribs 
crossed at fairly regular intervals by transverse flat ridges. Ventral 
slope marked by numerous incurved ridge-like growth lines. 
Length (approximate, minus the extreme point of the umbo), 
15 • 5 mm. ; greatest width, 7 mm. 
Observations . — This is a small species of Pinna which, in its 
strong convexity, narrow umbonal area, and the general outline 
resembles P. cordata, Pritchard*, with the exception that our shell 
is of a more oblong form. P. reticosa is distinct in having the dorsal 
ribs transversely cancellated by flat ridges parallel with the growth 
lines. The above form differs from P. semicostata, Tate,f in the 
relative narrowness of the proximal part of the shell, and the absence 
of scales on the ribs. Professor Tate has also recorded a species 
of Pinna (sp. indet.) from the Calciferous sandrock, River Murrav 
cliffs, near Morgan, which agrees generally with the above-named 
species P. reticosa, and he gives the following description^ : — 
Apical portions only known. Valves acutely angulated, with 
faint longitudinal ribs separated by broad interspaces on the 
ventral slope, crossed by undulose ridges.” 
From the polyzoal limestone of Seal River, King Island. 
Vulsella laevigata, Tate. 
V. laevigata, Tate, 1886, Trans. R. Soc., S.A., Vol. VIII p 29 
pi. iii., figs. 3 a, b. 
A. right valve, somewhat imperfect, occurs in the polyzoal rock? 
It is interesting to record this form in the King Island 
material, since it has only been noted hitherto from the lower beds 
at Aldmga. 
-tEcten aldingensis, Tate. 
P. aldingensis, Tate, Trans. R. Soc., S.A., Vol VIII 1886 
p. 16, pi. vii., figs. 1 a-c. 
Two typical valves of this species are found in the present series. 
The larger specimen shows, towards the front margin, some distant, 
concentric lamellae traversing the ribs, a character mentioned by 
late m his original description of the species. J 
It is interesting to find the above species in the present series 
smce, with the exception of Stansbury, S.A., Tate’s original record 
appears to be the only other locality known, viz., Aldmga Bay 
South Australia, in glauconitic limestone (Lower Aldingan) 
Found in the polyzoal rock, Seal River. 
* Proc. R. Soc., Victoria, vol. vii. (N.S.), 1895 d ‘’as nl « . _ 
t Trans. R. Soc., South Australia, vol. viii., 1886, p 29 pi xli to. V' 
t Loc. supra cit., p. 30. 1 ’ P xu ” b S ■ 9 - 
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