LIOPLAX. 



57 



from Mr. Shuttleworth. The original description given below, 

 and the copy of the fignres (Fig. IIG) confirm my opinion of its 

 identity with Mr. Lea's shell. 



Since the publication of this paper in the form of proof, Mr. 

 Gill has criticized my opinion of the identity of Pal. elliotli with 

 P. cyclostomatiformis. His opinion was not based on an exami- 

 nation of specimens, and has since been changed on seeing the 

 Smithsonian series. 



Paludina elliotli, Lea (I. c), — Shell subcari- 

 nate, pyramidal, rather thick, greenish-olive, 

 smooth, very narrowly umbilicated ; spire ele- 

 vated, subacute, flesh-colored at the apex ; sutures 

 excavated ; whirls 7, rounded, obtusely carinated 

 above, rather small ; aperture subrotund, small, 

 white within. 



Othcalooga Creek, Ua. Bishop Elliott. {Leu.) 



Pdludina elliotti. 



Fig. 116. 



Paludina contorta. 



Paludina contorta, Shuttleworth (J. c). — Shell 

 non-rimate, cylindrically conic, subovate, shining, greenish with olive lines ; 

 apex eroded ; whirls 6, strongly convex, divided by a deep suture, the mid- 

 dle ones carinated in the middle ; aperture oblong, 

 white ; peristome straight, acute, curved above. 



Shell smooth, cylindrical-conic, turreted with a 

 truncated apex ; shining, green, with olive brown 

 lines and strise ; sutures deep ; whirls 6, ventricose, 

 moderately increasing above, rapidly so towards 

 the base, the middle ones clearly carinate in their 

 centre, with brown angular curving strise and lines 

 at the middle keel ; last whirl shorter than the 

 penultimate, and near the upper portion of tlie» 

 aperture separated so as to form a deep groove of the suture. Aperture 

 longitudinally rounded, inner lip appressed ; peristome straight, acute, 

 twisted above (fig. 9), curving again below its centre, beautifully rounded 

 below and regularly blending with the columella. Height 8'", breadth 5 '". 



Alabama (Rugel), coll. Charpentier. (Kiister.) 



Reeve, /. c, adopts the same view of Pal. elliotti and contorta 

 as I have done. 



No. 9147 of the collection is almost ecarinate, and nearer Mr. 

 Lea's type of cyclostomatiformis than elliotti. 



It is singular that the only two known species of Lioplax 



should share the peculiarity of having a strongly carinated form 



with perfect apex, as well as a form with rounded whirls and 



truncated apex. 

 16 



