112 PALEOZOIC PALEONTOLOGY. 
bodies have a slightly constricted, encircling band, nearer to one 
extremity than to the other. It is difficult to determine with cer- 
tainty what these objects have been, but they suggest the shells of 
Foraminifera. 
MOLLUSCOIDEA. 
BRACHIOPODA. 
LINGULELLA STONEANA Whitt. ’ 
Plate I., Fig. 6. 
1882. Lingulella stoneana Whitf., Geol. Wis., vol. IV., p. 344, pl- 
27, figs. 6-7. 
Description.—Shell subovate to subpentagonal in outline, longer 
than wide, the beak rather blunt. The surface of both valves marked 
by concentric lines of growth, which are usually crowded and much 
more conspicuous near the margin, and also by fine, sharply-elevated, 
somewhat wavy ridges, which extend directly across the shell trans- 
versely from margin to margin, being nearly at right angles to the 
concentric growth lines at the margin, and becoming parallel with 
them along the medium line of the shell. The transverse lines become 
obsolete towards the anterior portion of the shell, but posteriorly about 
four or five of them occupy the space of 1 mm. In one specimen, near 
the centre of the anterior margin of the shell, fine, rounded, radiating 
strie may be detected. 
The dimensions of a nearly perfect valve are: length, 8.33 mm.; 
width, 5.5 mm. Other fragmentary specimens must have had a length 
of 10 mm. or more when complete. 
Remarks.—This species is especially characterized by the peculiar 
transverse markings of the shell, which are entirely independent of 
the lines of growth. It has heretofore been recorded only from the 
upper Cambrian strata of Wisconsin, and was first illustrated by Hall* 
as a variety of Lingula aurora. In Hall’s illustration of the shell the 
transverse markings do not pass directly across the valve from margin 
to margin, but they form a rounded angle, directed toward the beak 
* Sixteenth Rep. N. Y. State Cab. Nat. Hist., pl. 6, figs, 6-8. 
