ANIMALS. 57 
Schlotheimu, and other fossils occurring at Tunstall Hill and Humbleton. A few 
imperfect casts have occurred to me in the (? Rauchwacke) Limestone beds exposed at 
low tide, opposite Hendon, near Sunderland: they may belong to a different species. 
SERPULA (?) PUSILLA, Geinitz. Tab. VI, figs. 7-9; Tab. XVIII, fig. 13 a, 4, ¢, dt 
ForaMINITES SERPULOIDES, (provisional), King. 1848. Catalogue, p. 6. 
SERPULA PUSILLA, Geinitz, 1848. Versteiner. Zechsteingebirg. und Rothliegend., p. 6, 
tab. ui, figs. 3-6. 
INCH. 
Length, <5 
Breadth, =, 
Thickness, 4 
— 
An oblong coil of sub-cylindrical, wire-like folds, white and granular. A central, 
irregularly-twisted mass, of about 2, inch in diameter (see fig. 13 c), is inclosed in eight 
or nine outer folds ; these are flat or slightly concave on their internal surface, and 
convex externally, and are arranged longitudinally, not all on the same plane, but, 
with the exception of the outermost folds, crossing each other at the extremities of the 
coil at nearly right angles.” The size of the folds gradually increases from within 
outwards, but is subject to irregularities. 
This minute fossil appears to be the cast of a tubular shell, there beg more or 
less space between each of the larger folds, which are in consequence rendered 
extremely brittle. The shell, probably, was free and unattached. It sometimes occupies 
an oblong, smooth cavity, which is not, however, excavated in any shell or foreign 
substance, but appears to have been formed by the removal of the shell of the Annelid 
after it was surrounded by the calcareous deposit. 
This little fossil appears to be identical with the species figured and described 
by Geinitz (loc. cit.) as Serpula pusilla, from the Lower Zechstein of Corbusen, near 
Ronneburg. 
It is of frequent occurrence in the Limestone at Humbleton. 
. By Mr. T. Rupert Jonzs. 
2 The outer folds of this fossil bear some resemblance to those of the shells of some of the Agathistegia, 
M. d’Orbigny’s sixth Family of Foraminifera. The structure and arrangement, however, both of the inner 
and the outer coils, present such important differences from the essential characters of the Foraminifera 
referred to, that we can only be allowed this passing remark on the subject. 
h 
