CYCLOSTOMA. 305 



SHELL globose-oval, rather solid and opaque, scarcely glossy 

 (owing to the strong sculpture), yellowish-brown with more or 

 less of a reddish tinge and of ten marked with irregular streaks 

 or spots of reddish-brown or purple, sometimes plain yellow or 

 fawn-colour ; the spots sometimes form three or more indis- 

 tinct and interrupted rows on the body whorl ; sculpture 

 consisting of strong spiral ribs, of which there are about forty 

 on the last whorl, and of much finer but more numerous trans- 

 verse ribs, which do not cross the main ribs but intersect the 

 interstices, giving that part of the surface a somewhat reti- 

 culated appearance : periphery rounded : epidermis thin : 

 whorls 4 J, exceedingly tumid, the last occupying considerably 

 more than two-thirds of the shell; upper whorls purple or 

 yellowish-brown and quite smooth : spire bluntly pointed : 

 suture very deep : mouth circular, with the exception of a slight 

 angle at the upper part : outer lip and inner lip rather thick, 

 very slightly reflected, and forming a complete peristome : 

 umbilicus twisted, but rather deep : operculum flat, composed 

 of about five whorls, strongly and closely marked with oblique 

 and flexuous striae; nucleus depressed, smooth, and of a darker 

 colour, like the nucleus or apex of the shell. L. 0'6. B. O4. 



HABITAT : Under stones and at the roots of fern and 

 furze in many parts of England, Wales, and Ireland, 

 from Yorkshire to Alderney. It appears to frequent 

 chiefly the sea-coast and calcareous soils ; but it occurs 

 in Northamptonshire and Oxfordshire (inland counties), 

 as well as in parts of Norfolk where there is no chalk. 

 It has not been recognized with any degree of certainty 

 as a fossil of our upper tertiaries. Its foreign range is 

 southern, and includes Central Germany, France, Italy, 

 and Portugal ; and it extends to the Canaries. Donegal 

 Bay appears to be its most northern limit. 



Lister gave, nearly two centuries ago, some excellent 

 details of the physiology of this mollusk ; and in 1828 

 another of our countrymen (the Rev. M. G. Berkeley) 

 published, in the ' Zoological Journal' (vol. iv. p. 278-284), 

 further particulars of its anatomy. According to Moquin- 

 Tandon it is a vegetable feeder ; and the structure of its 



