The Hou.^E. Cbitty on the Stoastomidre. 147 



Petitia Adamsiana, Cliitty. 



Jlab. New Hope, Old Hope, and a smaller variety on the road 

 east of the "Water-wheel," Westmoreland. 



i''o?7H, glohose-discoidal. C'o/o?//*, reddish horn. Sculpture, 13 very 

 strong S})iral earintc, with hetwcen the 1st and 2nd and '2nd and 3rd, 

 1 each rather less strong ; between the 3rd and 4th and 4th and 

 5th, 3 each less strong ; between the .0th and Gth, 1 less strong ; 

 between the (Jth and 7th, 3 less strong ; between the 7th and 8th, 

 1 less strong, and none between the remaining strong carinrc. Lines 

 of growth very faint ; on the upper whorls, 4 strong carinse with in- 

 tervening less strong. Spire, slightly elevated, with rather convex 

 ontlines. Whorls, 4.V, very slightly rounded and with a very slight 

 suture ; last whorl slightly swelling behind the labrum, and slightly 

 constricted at the aperture. ^Jperture, vei*y slightly expanded and 

 scarcely detached from the penult whorl. Labrum, appressed to the 

 body-whorl, not produced nuich thickened, slightly double below ; 

 smooth and simple. Labimn, much thickened and reflected towards 

 the vuubilicus in its centre, slightly curved to the right below ; well 

 detached from the body-whorl. Umbilicus, moderately deep, co- 

 vered by an expansion very convex externally of the lahrul lamella, 

 which is much produced immediately after leaving the labrum, and 

 then becomes abruptly narrowed till it joins the body -whorl. In the 

 labral lamella it approaches the subgenus Ayassizia. Operculum, 

 very peculiar, deeply concave in the centre and studded with very fine 

 granulations ; edge all round very much thickened and folded over 

 in vertical jjlaits outside, especially at the lower end of the labial 

 side ; throughout the labial side overlapping the labium with sharp, 

 fine, nnmerous raised lamellfe on the labral side. 



Height 0-0G2, greatest breadth O-O!), least breadth 0'077. 



Var. a. 



From near " Water Wheel." 



Height ()-044, greatest breadth 0-076, least breadth O-QGl. 

 Named in honour to the memory of the late Professor C. B. 

 Adams of America, my friend and conchological master. 



Petitia Tayloriana, Chitty. 



Hab. ? St. Ann's. 



Form, globose-discoid. Colour, pale horn. Sculpture, 24 fine, 

 sharp, incquidistaut, spiral carinsc, G of which interspersed are rather 

 strong ; on the upper whorls 5. Spire, very slightly elevated, with 

 convex outlines. Whorls, 4, slightly rounded, with a slight suture. 

 A])erfure, very slightly constricted behind the labrum, and slightly 

 expanding ; scarcely detached from the body-whorl ; slightly de- 

 pressed above and expanded below. Labrum, white, shortly reflected, 

 not produced above, very little pectinated by the stronger spiral 

 carinse ; slightly double below. Labium, on a plane with labrum, 

 straight, aj)pressed above to the body-whorl. TJmbilicris, rather 

 deep and narrow. Labral lamella, scarcely produced. Opercidumi 



10* 



