Inferior Oolite in Gloucestershire, 417 



two encircling nodose ribs, one at each margin of the whorl, and three 

 mesial circles of nodnles. 



38. Trochus alternans ; moderately elevated and costated, three 

 nodulated costae upon each whorl, the middle one the smallest. 



40. Trochus cinc/illato-serratus ; whorls few, bicarinated, the lower 

 carina much the larger, the intermediate space concave with small 

 serrated circles of ribs ; the carinte are longitudinally serrated. 



41. Trochus pileus ; very elevated ; whorls few, concave, with lon- 

 gitudinal elevations united at the base, and overwrapping the upper 

 portion of the succeeding whorl, base discoidal. 



42. Trochus infundibuliformis ; figure a low cone above, discoidal 

 beneath ; whorls three or four, flattened, with numerous obscure lon- 

 gitudinal wrinkled lines. 



41 & 42. These two remarkable species are placed provisionally in 

 the genus Trochus ; it is probable however that they will ultimately 

 be erected into a new genus. 



44. Pleurotomariafunata ; elevated ; whorls five or six, convex 

 above, but rather flattened at the sides, with numerous equal, closely 

 arranged angular encircling ribs decussated by fine longitudinal lines. 

 Fascia of the sinus broad, striated longitudinally, with an encircling 

 elevated line bounding it upon each side. 



45. Pleurotomaria laevigata ; discoidal ; whorls five, smooth, 

 slightly convex ; fascia of the sinus narrow, forming a slightly convex 

 band ; base smooth and discoidal. 



46. Trochotoma carinata; moderately elevated, acuminated; 

 whorls narrow, numerous, angulated, rendered concave both above 

 and below by an elevated and acute carina ; the first three or four 

 whorls have closely arranged encircling striae crossed by others longi- 

 tudinal, but the larger whorls are perfectly smooth, or have only the 

 oblique lines of growth ; the carina is formed by two parallel lines ; 

 the base is widely and deeply excavated ; height f ths of the basal 

 diameter : rare. 



47. Trochotoma depressiuscula ; depressed; whorls five, narrow 

 and angulated ; ribs below the angle three, above more numerous ; 

 upper surface of the whorls concave, lower flattened ; base striated, 

 excavation large, not deep ; height half the basal diameter : rare. 



49. Trochotoma funata ; elevated, acuminated, nearly smooth ; 

 whorls convex, their lower portions flattened, with numerous encir- 

 cling granulated ribs, faintly traced, basal excavation contracted. 

 Height about equal to the basal diameter. 



51. Natica canaliculata \ ventricose ; spire elevated ; whorls five, 

 acute, flattened at their sides, their upper surfaces deeply channeled, 

 the angle of the whorls slightly tumid ; aperture obliquely ovate ; axis 

 imperforate, last whorl very large and tumid ; axial diameter 1 inch 

 4 lines, transverse 1 inch. 



54. Phasianella acutiuscula ; ovate ; spire small, acute, with four 

 very narrow rather convex whorls, whose upper borders are disunited 

 from the preceding whorls ; body-whorl much expanded and globose ; 

 aperture large, f rds the axial length ; axis 5 lines, transverse diameter 

 4 lines. 



Ann. Ss May. N, Hist. Ser. 2. Vol\i. 28 



