260 NEW FOSSIL SHELLS 
Remarks.—On the upper part of the spire the angle of the whorls is near their middle. 
Below, it is close to the superior suture. The ribs rise, near the upper part of the 
whorls, to a short spine, and descend rapidly to the suture, where they become obsolete. 
The mouth is small and nearly round. 
This little shell I at first thought to be merely the young of S. pachypleura, Conrad; 
but, as it is but one fifth the size of that species, with the same number of whorls, they 
cannot be identical. 
S. MIcROPLEURA, PL. 36. Fic. 67. 
8. testa elevato-pyramidali, tenui, imperforatd, costulatd; spird attenuatd, conicd, obtusd; suturis parvis, linearibus; an- 
fractibus sex, convexis; costis minutis, crebrissimis; anfractu ultimo rotundato; basi levi; aperturd ovatd, marginibus su- 
perne disjunctis; labro acuto. 
Shell elevately pyramidal, thin, imperforate, costulate; spire attenuate, conical, obtuse; sutures small, linear; 
whorls six, convex; ribs very small and numerous; last whorl rounded; mouth ovate, with the margins disunited 
above; outer lip acute. 
Length .10. Breadth .05 of an inch. 
Remarks.—I have felt some hesitation in placing this shell among the Scalariz, as the 
small coste and incontinous peritreme of the mouth seem scarcely to warrant it. 
S. microstoma, Pr. 36. Fie. 68. 
S. testa subulato-conicd, ten, imperforatd, costatd; spird conicd, valde attenuata, obtusd; suturis impressis, interruptis; 
anfractibus septem, valdé convexis; costis raris, elevatis, reflexis; anfractu ultimo rotundato; basi sub-carinatd; apertura 
parva, obliqud, sub-rotunda; labro valdé incrassato. 
Shell subulate-conical, thin, imperforate, costate; spire conical, very attenuate, obtuse; sutures impressed, inter- 
rupted; whorls seven, very convex; coste few, elevated, reflexed; last whorl rounded; base sub-carinate; mouth 
small, oblique, sub-rotund ; outer lip very much thickened. 
Length .28, Breadth .12 of an inch. 
Remarks.—The carina of the base is very small; it does not cross the cost#, which 
continue to the columella, The mouth is unusually small and nearly round. The 
costé are ten in number on the last whorl, quite prominent, and reflexed. In full grown 
specimens the one which forms the outer lip is much thicker than the rest. The ribs of 
one whorl do not join those of the next, but lap over very closely. This causes the 
sutures to be continually interrupted. 
This shell bears a close resemblance to S. acicula, herein described, but differs in be- 
ing more subulate, having fewer and reflected ribs, and a smaller basal carina. 
GENUS DELPHINULA. 
D. costuLatTa, Pu. 36. Fic. 69. 
D. testé orbiculari, depressd, crassd, costatd, striata; spird brevissimd, acumi ald, aculd; sutwris linearibus; anfractibus 
sex, valde conveais, suprdé planulatis et lavibus; costis parvis, crebris, transversis, politis; striis longitudinalibus, obliquis, 
minutissimis; anfractu. ultvmo rotundato; basi costaté ; umilico magno, profundo, intus levi; apertura rotundd, supra sub- 
conaliculata. 
Shell orbicular, depressed, thick, costate, striate; spire very short, acuminate, acute; sutures linear; whorls six, 
very convex, smooth and flattened above; costs transverse, small, numerous, polished; strix longitudinal, oblique, 
very minute; last whorl rounded; base costate, umbilicus large, deep, smooth within, mouth round, sub-canaliculate 
above. 
