SILURIAN 
14 
tion) is found in more than one Welsh species of Lower Silu¬ 
rian date. 
The shell is slightly curved, very conical from its rapid 
tapering, and appears to be contracted towards the last cham¬ 
ber. The section is regularly broad-oval ; the siphuncle quite 
external and rather large. The septa are not oblique, rather 
close, concave, considerably arched backwards on the sides, 
a nd therefore projecting forwards on the ventral and dorsal 
aspects. They are crowded on the inner side of the curve, 
and of course wider apart on the outer margin. 
The whole fragment is 2 inches long; the last chamber is 
not preserved in our single specimen, nor have we the pointed 
apex, which was probably more curved than the older part of 
the shell. (Fig. 1 a. is a section of the smaller end.) 
Locality .— (1720) Rimkin. 
LITUITES IULIFORMIS. 
Plate 2, fig. 2. 
L. discoidalis, anfractibus 5 fere liberis convolutis, subquadratis, 
quam profundis | latioribus ; dorso subpiano convexiusculo ; lateribus 
obliquis, ad umbilicura declivibus, angulis externis projectis. Septa 
simpliciter arcuata, leute concava ; sipho internus fere marginalis. 
Strife asperte confertse. 
Discoid, and very much flattened; our solitary specimen, an 
inch and three-quarters in diameter, having at least 4 or 5 con¬ 
tiguous but not embracing whorls, which are squarish in sec¬ 
tion,—about two-thirds as deep from back to front as wide ; 
somewhat flattened on the sides sloping to the umbilical 
margin, very blunt and flat on the back, and gently concave 
on the inner edge. Surface with undulating sharp unequal 
strise of growth. The siphuncle is quite internal, almost 
touching the inner border. Septa rather distant, in whorls 5 
lines deep nearly 2 lines apart, not very convace, moderately 
arched backwards on the sides, and straight, or only gently 
curved across the back. 
