WiLckENS.— аһа and other Fossils from the Upper Senonian. 539 
Lahillia and some other Fossils from the Upper Senonian of New 
Zealand. 
By Отто WiLckENs, Ph.D., of Bonn University. 
Communicated by P. G. Morgan. 
[Read before rd Wellington Philosophical Society, 13th June, 1923; received by Editor, 
nd December, 1923 ; published separately, 16th August, 1924.] 
Plate 54. 
SoME time ago I received for examination from Mr. P. G. Morgan, Director 
of the Geological Survey, through Mr. J. Marwick, Palaeontologist, some 
fossils from apes localities in the South Island of New Zealand. I am 
much indebte Mor, or the transmission of this interesting 
materia], vici Wa as collected at the orig localities : 13 (Amuri os я 
МсКау, 1873 and 11876). ; 22 (Green Island, near Dunedin, McKay, 1873) ; 
589 (Selwyn River Rapids, Malvern Hills, McKay, 1886) ; 592 (Shag Point, 
beach near coal-mine and McIntosh’s store, McKay, 1886); and 320 (Shag 
Point, Hector, 
e conclusion reached after an examination of these fossils is that all 
the localities represented are of Upper Senonian age. 
DESCRIPTION OF THE FOSSILS. 
LAMELLIBRANCHIATA. 
LAHILLIA Cossm. 
Lahillia cf. luisa O. Wilck. sp. (Plate 54, figs. 1, 2, 3, 4.) 
Outline of shell oval. Umbones very prominent, curving strongly 
inward and very slightly forward, xu situated a little behind middle of 
dorsal margin. Shell inflated, anterior portion somewhat flatter than 
posterior and somewhat produced. Anterior margin considerably convex, 
passing gradually oe ет дак convex ventral margin. Posterior margin 
less rounded than rior and somewhat truncated.  Antero-dorsal and 
postero-dorsal dene concave. Lunule flat. cogn consists of 
хта coarse concentric ridges at wide intervals, and of thin growth-lines 
terspaces, well preserved on ventral portion of shell, while the coarser 
тад are less wine ges in this region. Muscular impressions not visible. 
One Spem shows portion of ligamental groove (Plate 54, fig. 4). 
of right vive. “(Plate 54, fig. ree rtly preserved in os from 
u Ao il 
downward and forward. Grooves on both sides of this tooth, destined 
for cardinal teeth of left valve, are more or less well preserved, but lateral 
teeth are royed. 
Specimen from locality 589 shows portion of hinge of left valve (Plate 54, 
fig. 4). In this specimen the considerable thickness of the shell is visible, 
which is a character of the genus. (It is a consequence of this thick- 
ness that umbones of casts are more prominent than those of — 
Ventral margin of hinge-plate well preserved, but teeth more o 
damaged. Most conspicuous is the large groove fa triangular stan 
