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300 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Mar. 6, 



3. Rissoa Leigili, Brown. PI. VII. figs. 1-6. 



R. Leighi, Brown, Trans. Manchest. Geol. Soc, vol. i. p. 64, pi. 6. 

 figs. 9-11. 



Syns. Rissoa Gibsoni and R. pusilla, Brown. 



Typical specimens of this minute species are ovately conical in ge- 

 neral form ; with four, or rarely five, flatly convex smooth whorls, 

 that increase quickly in length and width, and which are divided hy 

 a deepish and slightly oblique suture. One half of the length is oc- 

 cupied by the body-whorl, which has a well-rounded basal slope ; 

 the spire is conical, with rather a blunt apex. The aperture is 

 nearly oval and of moderate size, the outer-hp being strongly arcuate, 

 the pillar-hp somewhat curved, and reflected, with a slight umbilical 

 chink behind it. 



Length -t- inch ; breadth 



There are other specimens almost obovate in form, with convex 

 whorls, more depressed spire and obtuse apex. Others, again, have a 

 large body- whorl, rounded whorls, and also an obtuse apex. 



An examination of a type specimen of Rissoa Gibsoni from the 

 Lancashire Permian beds (kindly lent me by Mr. Binney) has led me 

 to place that species along with the one I am noticing, of which it 

 seems to be but an enlarged form. 



The Trochus pusillus, Geinitz, of the L T nter Zechstein, is a related 

 form, but undoubtedly distinct from the present. So it would ap- 

 pear is the Turbo Permianus, King, of the Shell-limestone of Durham. 



Rissoa Leighi has only occurred to me at Hampole, where it is not 

 rare in the beds containing Turbo helicznus. It is found in greater 

 plenty in the Permian marls and limestones of Colyhurst near Man- 

 chester*. It has also been met with under its Gibsoni form by Prof. 

 King, at Tullyconnellf. 



4. Tureitella Altexbukgexsis, Geinitz. PI. VII. figs. 9, 10. 

 Turbonilla Altcnburgensis, Geinitz, Verstein. deut. Zech. p. 7, 



tab. hi. figs. 9, 10. 

 Syns. Looconema fasciata, King ; L. Geinitziana, King ; TurriteUa 

 Phillipsii,Ho\?se; T. Tunstallensis, Howse; and Rissoa gracilis, 

 Schauroth. 



Specimens of a minute turreted shell are not rare in the Lower 

 Limestone at Hampole. Like the individuals of other Gasteropods 

 from this locality, they are evidently young individuals, and some- 

 what stunted in growth. 



These specimens are minute, turreted, and smooth. They have 

 only five whorls, rarely six, which increase gradually in length, and 

 somewhat quickly in breadth. The whorls are ventricose and equally 

 rounded ; the suture is deep, rather wide, and oblique. The body- 

 whorl is about as long as one-third of the entire length. The aper- 

 ture, which occupies rather more than one-fourth of the length of 

 the shell, is obovate, being rounded behind and rather produced in 



* Messrs. Binney and Brown in Trans. Manch. Geol. Soc, vol. i. p. 63 ; and 

 Prof. King in Mon. Perm. Foss. of England, pp. 205, 206. 

 t Journ. Geol. Soc. of Dublin, vol. vii. 



