CERITHIUM. 163 
Shell slender, pupoid, turrited. The spiral angle ranges from about 20° at 
the opening to 13° in the anterior portions of the spire. Whorls numerous, 
narrow and flattened. Sutures distinct. The subapical whorls are-ornamented 
by three granulated spirals, which in the anterior whorls are increased to the 
number of five or six. The spirals undulate and decussate, with short and not 
prominent cost at regular intervals, producing a very pretty basket-shaped 
pattern. There is some irregularity in the development of these spirals, the 
uodulations of the upper row being always the strongest. 
The body-whorl is about one-third the length of the shell, compressed, and 
with ornaments similar to those of the spiral whorls (in the figured specimen 
these have suffered from wear). Aperture subquadrate, with a short, stout 
anterior canal. 
Relations and Distribution.—Closely related to the limzxforme section of the 
group. Specimens somewhat resembling C. Georgii occur in the Corallian of 
England and possibly also in the Great Oolite. We may regard such either as 
distinct species, or as megalomorphs of the prevailing form. Named after 
Mr. George, curator of the Northampton Museum. Rare in the Lincolnshire 
Limestone. 
87. CERITHIUM SUBCOSTIGERUM, sp. nov. Plate IX, fig. 11. 
Description : 
Length ; : : . 8mm. 
Width : . : . 2°75 mm. 
Shell short, subpupeform, slightly turrited; number of whorls about seven, 
subconvex, and separated by a wide and shallow suture. Apex obtuse. The 
ornaments consist of numerous fine spiral lines, so fine as to be scarcely visible in 
the upper part of the whorls. hese are decussated by robust coste, which 
extend from suture to suture, being, however, strongest towards the posterior 
margin of each whorl. These costw have a kind of twist from left to right, and 
do not follow in true sequence. 
The body-whorl somewhat exceeds one-third the total leneth of the shell, and 
its flanks are similarly ornamented. Base full, spirally striated, but without any 
axial lines. Aperture subquadrate; other indications wanting. 
Relations and Distribution —This species has some resemblance to Hrelissa 
(Kilvertia). On the other hand, it also has relations to some varieties of the 
limxforme-group, where the tuberculations have a tendency to fuse throughout 
into axial coste. Only found, to my knowledge, in the lancolnshire Limestone, 
