NEWTON: ON BORNEAN JURASSIC SHELLS. 407 
This species is largely represented in these beds, and is the most 
abundant shell in the present collection. It occurs both in the 
ferruginous red-clay formation and in the siliceo-pyritized rock. 
3. Prorocarpia TEeNuIcostaTa, F. Vogel. 
Protocardia tenuicostata, Vogel: Samml. geol. R.-Mus. Leiden, vol. v 
(1896), p. 142, pl. ix, figs. 6, 7; vol. -vi (1900), p. 58, plo n, 
figs. 4-6. 
The collection contains only a fragmentary example of this species, 
although quite sufficient for purposes of determination. It displays 
the typical sculpture with the closely-set vertical striations between 
the fine and numerous concentric coste. It occurs in the ferruginous 
red-clay deposits. 
4. Arca sp. 
Arca sp., Vogel: Samml. geol. R.-Mus. Leiden, vol. vi (1900), p. 50, 
pl. ii, fig. 16. 
An impression of a portion of a valve of this shell, from which 
a wax squeeze has been made, gives the shape and concentric striations 
as described and figured by Vogel. It is found in the grey-coloured 
cindery rock. 
5. Corsuta VogEri, Cossmann. 
Corbula Borneensis, Vogel: Samml. geol, R.-Mus. Leiden, vol. v (1896), 
pp. 144-146, pl. x, figs. 1-3; non Boettger, 1875, nec Krause, 1897. 
Corbula Vogeli, Cossmann: Revue Critique Paléozoologie, 1900, p. 12. 
The grey-cindery rock contains impressions of a shell exhibiting 
the close and regular concentric sculpture characteristic of this species. 
6. Psrvpomonotis sp. (Pl. XVI, Fig. 7.) 
A fragment of this genus occurs in the grey-cindery rock, accom- 
panied by other shell remains and articular impressions of crinoidal 
stems. It represents a portion of the lower valve (about 10 mm. in 
length), with 8 or 10 diverging, longitudinal, rounded nbs, some of 
which appear to bifurcate about midway. These ribs are furnished 
at frequent and regular intervals with short open spines or fistulosities. 
The intercostal spaces are crowded with minute transverse striations. 
The only shell this fragment appears to resemble is the Pseudomonotis 
echinata of J. Sowerby, of Lias and Lower Oolite age. It was thought 
to be worthy of reference on account of the beautiful sculpture it 
exhibits. 
7. Evsprra Borneensis (F. Vogel). 
Amauropsis Borneensis, F. Vogel: Samml. geol. R.-Mus. Leiden, 
vol. v (1896), p. 149, pl. x, figs. 7,8; vol. vi(1900), p. 67, pl. iv, 
fig. 5. : 
Euspira Borneensis, Cossmann: Revue Critique Paléozoologie, 1900, 
Digts. 
This species, of which there are several examples in the collection, 
occurs in the red-clay beds. It possesses a prominent tabulate spire, 
with traces of sub-vertical striations of growth. M.Cossmann regarded 
VOL. V.—OCcTOBER, 1903. 28 
