8 
Norman, on Diatomacecs. 
large quantity of tlie material, when it is to be hoped that it 
may prove more abundant. The blank centre, large size, and 
unusual distance from the margin of the nodules, together 
with the large blank spaces around the same, render this a 
well-marked species. 
Judging from the occurrence, in abundance, of the various 
species of Heliopelta in this deposit, together with Eupodiscus 
Rogersiij Craspedodiscus elegans, Aulacodiscus Crux, Scep- 
troneis caduceus, Triceratium solenoceros, condecorum, undu- 
latum, and acutum, there can be little doubt that it is 
identical with the Bermuda earth of Professor Bailey, the 
locality of which has hitherto remained in much doubt. For 
the small quantity received I am indebted to Messrs. Sulli- 
vant and Wormley, of Columbus, Ohio. The deposit was 
discovered, I believe, by Dr. Johnson, of Baltimore, near 
Nottingham, in Maryland, not far from the Patuxent Biver, 
and within a moderate distance of Piscataway, where the well- 
known rich deposit occurs. 
Bermuda Hundred, on the James Biver, in Virginia, is 
distant about a hundred miles from Nottingham, but as all 
the waters of this district find their way into the great 
Chesapeake Bay, it is quite possible that the locality suggested 
by Dr. Arnott may have furnished the sample of Bermuda 
earth originally sent to this country by Dr. Bailey. I under- 
stand, however, from Messrs. SuUivant and Wormley, that 
Dr. Johnson had examined the country at Bermuda Hundred 
without finding any deposit whatever. When the larger 
supply of the Nottingham material arrives, I shall be glad to 
supply my friends with a portion. 
6. Eupodiscus ovalis, n. sp., Norm. (Fig. 7). — Valve 
elliptical, nodule single, submarginal; granules arranged 
in radiating lines, crowded near the margin, sparser towards 
the centre. Colour, tawny brown. Length of valve -0020" 
to -0035." 
Marine, stomach of Ascidians, Shark Bay, Australia. 
This species approaches Eupodiscus fulvus, differing, how- 
ever, in the elliptical shape, altered position of the nodule, 
which in the latter is nearer the margin, and also in the 
arrangement of the granules, the disc being divided into 
regular segments by the longest lines of granules. 
7. Navicula bullata, n. sp.. Norm. (Fig. 6). — Valve 
elliptical, extremities slightly produced. Strise in a marginal 
and two central bands ; marginal bands of unequal width. 
The smooth space between the striated bands studded with 
a line of circular bosses. Strise moniliform, 14 in '001". 
Length of valve -0065"; breadth '0030''. 
