1 68 HE LIC IDA?. 



In the British Isles this genus is represented by a 

 single species only. 



Gwyn Jeffreys considers that the word Balia is 

 derived from balius, a corruption of the Latin word 

 badius (brown), " and not, as Bourguignat supposed, 

 from ySaXto? (maculostis, spotted), as the shell is not 

 spotted " ; but it seems unnecessary thus to strain the 

 derivation, because the signification of the Greek 

 word is not restricted to spotted ; $a\io<s also means 

 striped, or streaked, which terms are quite as appli- 

 cable to the shell as " bay-coloured." 



BALIA PERVER'SA,* LINN. PL. IX. 



Body lanceolate, dark brown tinged with grey ; tubercles black, 

 very minute and rather wide apart ; tentacles short, slaty-grey, 

 upper pair finely granulated and almost united at their base, 

 bulbs somewhat oval ; lower tentacles slightly diverging, much 

 smaller, lighter in colour and more transparent than the others ; 

 foot broad, slightly rounded in front and ending in a slightly 

 keeled tail; lingual ribbon with 130 rows of 41 teeth - 5330. 



Shell club-shaped, thin, semitransparent, glossy, yellowish 

 horn-colour streaked with white, with numerous close-set, 

 irregular striae in the line of growth ; periphery faintly angulated ; 

 epidermis moderately thin ; whorls 7-8, gradually increasing in 

 size, convex but very slightly compressed ; spire produced, apex 

 obtuse and (as is also the whorl below it) devoid of striation, and 

 highly polished ; suture deep ; mouth forming about three- 

 fourths of an oval, with occasionally (in adult specimens) a small 

 tooth-like protuberance, which is situated near the middle of the 

 base of the penultimate whorl ; outer lip thin, whitish, slightly 

 reflected ; umbilicus consisting of a narrow chink. 



Inhabits many parts of Great Britain and Ireland, 

 on the trunks and under the bark of trees, especially 



* Turned the wrong way. 



