i S8 
PALAEONTOLOGY OF NEW-YORK. 
Lingula spatiosa (n. s.). 
Plate IX. Fig. 10 & 10 a. 
Shell broadly ovate, with beak acute, base broadly rounded, and sides 
sloping in a gentle curve to the beak. Length a little greater than the 
greatest breadth, which is at a point less than one-third the length 
from the base. 
Surface, which is partially exfoliated, marked by fine equidistant con¬ 
centric lines, crossed by fine scarcely perceptible radiating lines (these 
lines are much too strong in the figure). 
Fig. 10. The shell, natui-al size. 
Fig. 10 a. A portion of the surface enlarged. 
Geological position and locality. In the slialy limestone of the Lower Helderberg 
group : Becraft’s mountain near Hudson. 
In certain parts of the shaly limestone in the Lower Helderberg group 
in Albany county, the lingulas are common fossils, occurring often in 
fragments, and not unfrequently in the centre of phosphatic nodules 
which have all the external aspect of coprolites. These masses sometimes 
contain a single shell of Lingula in the centre, with few or no fragments 
of similar shells in the surrounding mass; while others are composed of 
fragments of shells of lingulae with intermediate dark-colored impure 
carbonate of lime, which effervesces very slowly in acid. These bodies 
may probably be concretions where phosphatic material has aggregated 
around the Lingula, or a similar mass when fragments of these shells 
have formed the nucleus. The uniformly elongate oval or ovoid form, and 
usually vertical position in the strata, are remarkable and interesting- 
features. A chemical analysis may perhaps furnish some information 
suggestive of their origin. 
