418 Mr. J. Lycett on Fossil Shells from the 



55. Phasianella turhiniformis ; ovate, acute; whorls five to six, 

 convex, narrow, last whorl large, ventricose ; aperture large, oval, ob- 

 lique, its length a little exceeding half of the axial and f ths of the 

 transverse diameter. 



55*. Phasianella subangulata ; ovate, lengthened; spire pointed ; 

 whorls rather convex, few, body-whorl large, ovate, subangulated in the 

 middle ; aperture elongated and oblique, its length equal to the trans- 

 verse and f ths that of the axial diameter of the shell. 



57. Acteonina ovata ; ovate ; spire of moderate elevation, consist- 

 ing of four flattened whorls, last whorl subcylindrical, large ; aperture 

 lengthened, oblique ; axis 1 1 lines, breadth 6 lines. 



bQ. Acteonina tumidula ; spire small ; body- whorl very large and 

 tumid ; aperture expanded anteriorly ; axis 6 lines, breadth 4 lines. 



59. Cylindrites attenuatus \ conico-cylindrical ; spire short, acute, 

 of six whorls, which are very narrow and acute at their upper borders ; 

 body-whorl flattened and attenuated towards the base ; length 8 lines, 

 breadth 4 lines. 



60. Cylindrites gradus ; cylindrical, elongated ; spire elevated ; 

 whorls five to six, step-like, but slightly rounded at the angles, the 

 lower portions of the whorls perfectly flat. 



The above-named two species of Cylindrites have elevated spires ; 

 those which follow have sunk spires, but exposed, the upper edges 

 of the whorls being visible ; the apex, which usually comprises the 

 first two or three volutions, forms a kind of mamillary tubercle ele- 

 vated above the depressed edges of the other whorls except the last. 

 They constitute two very distinct sections. 



62. Cylindrites tabulatus ', conico-cylindrical, vertex large, but little 

 depressed ; whorls numerous, centre slightly mamillated and elevated ; 

 the figure is tuberose and the vertex unusually large. 



6 1 . Cylindrites mamillaris ; conico-cylindrical, elongated ; sides of 

 the body-whorl flat, its upper edge acute ; the inner whorls have their 

 upper flat surfaces visible, the first two or three of which are elevated 

 into a rounded or mamillary process. This nearly resembles a Great 

 Oolite species, but it is less elongated, and the vertex is more de- 

 pressed. 



63. Cylindrites hulhiformis ; very short or tun-shaped, the upper 

 surface wide and flattened, but the apex rises a little ; axis 4 lines, 

 transverse diameter 5 lines. 



64. Chemnitzia nitida ; small, smooth ; whorls five to six, convex, 

 body-whorl large, oval, aperture oblique ; length \ inch. 



^b. Chemnitzia elegans ; subcylindrical, smooth ; whorls nume- 

 rous, convex, but short, their breadth exceeding their length ; the 

 body-whorl is symmetrical and not enlarged ; apex unknown ; length of 

 fragment 3f inches, in which only the four last whorls are preserved. 



99. Chemnitzia gracilis ; spire excessively lengthened and acumi- 

 nated ; whorls very numerous, flattened or very slightly convex, longer 

 than wide, sutures marked, aperture ovately elongated, pointed ante- 

 riorly ; length 7 inches, diameter of last whorl 6 lines. 



Ceritella, a genus related to Cerithium, which will be illustrated 

 in a forthcoming monograph on the Testacea of the Great Oolite. 



