80 MOLLUSCA FROM THE GREAT OOLITE. 



minute or obsolete ; the upper border of the whorls has an obscure encircling row of 

 tubercles ; fascia of the sinus marginal ; the aperture quadrate. 



The delicate markings upon the surface are only visible under a magnifier. The general 

 figure and character of the surface nearly approximates to Pleurotomaria punctulata, 

 Deslongchamps, but in that species the fascia of the sinus is placed upon the middle of the 

 whorls, and it is destitute of the upper encircling band of tubercles. 



Axis 4 lines, basal diameter 6 lines. 



Locality. The white stone of Bussage has furnished our specimen, but the species is 

 very rare. 



Pleurotomaria composita. Plate X, figs. 13, 13«r. 



P. Testa turbinatd, conicd; spird subacutd ; anfractibus super tie couvexis, infra 

 planatis vel subconcavis ; sinu magno ; fascia sinus lata, longitudinal iter striata, in medio 

 anfractuum sitd ; anfractibus supra fasciam densissime longitudinaliter et oblique stria f is j 

 sfriis inaqualibus ; infra fasciam striis transversis aqualibus profundis subdistantibus ; 

 ayfractu ultimo ad basim rotundato ; facie infmd plana, vel subconvexd, longitudinaliter 

 tenuissime et inaqualiter undulatim striata; umbilico nullo? vel minima; aperturd sub- 

 pen tagonali. 



Shell turreted, conical ; spire subacute ; whorls convex in their upper portions, 

 flattened or slightly concave in their lower ; the sinus large, the band of the sinus wide, 

 longitudinally striated, and situated in the middle of the whorls ; the whorls above the 

 band are, longitudinally, densely and obliquely striated ; the striae are unequal ; beneath 

 the band the whorls are transversely striated ; the striae are equal, deeply impressed, and 

 rather distant ; the last whorl is rounded at the lower margin ; the base is flat or slightly 

 convex, it is longitudinally, densely, and unequally striated ; the striae undulate ; umbilicus 

 none or minute ; aperture subpentagonal. Axis 9 lines, basal diameter 1 1 lines. 



Locality. The lower weatherstone beds at Quarrhouse and Minchinhampton have 

 yielded several specimens. 



Troohotoma, Lycett. Deslony champs, 1842. 



Rimulus, WOrb. 1839. 

 Ditremabia, D'Orb. 1842. 



T. Testa turbinatd, conicd; anfractibus scepissime angulatis, in medio vittd strictd 

 notatis ; perip/iarid subangulatd ; aperturd subquadratd ; columella arcuatd ; basi eoccavatd, 



