26 COLLINGE : DESCRIPTIONS OF A NEW VARIETY. 



1891.— T. D. A. Cockerell. — [A. ambiguus in Dorset.] Brit. Nat., 

 p. 101. Mentions var. armoricana and A. circumscriptus form 

 nov. sub-albida, Ckll. 



1891. — T. D. A. Cockerell. — " Notes on A. hortensis, A. circum- 

 scriptus, and their allies." Conchologist, vol. i., p. 35. 

 Description of those specimens mentioned in preceding note. 



1892. — C Ashford. — Donation of Shells from Dorset. Journ. 

 Conch., vol. vii., p. 47. 



1892. — E. R. Sykes. — Exhibition of Shells from Dorset. Journ. 

 Conch., vol. vii., p. 48. 



DESCRIPTIONS OF 



A NEW VARIETY OF ARION HORTENSIS, FER., 



AND A. CIRCUMSCRIPTUS, JOHNST. 



By WALTER E. COLLINGE, 

 Assistant Demonstrator in Zoology, St. Andrews' University. 



Dr. Scharff has very kindly sent me a number of Irish Arionince, 

 amongst which are numerous examples of the blue form of Ariou 

 hortensis* and which I am now describing as a variety of this 

 species. Possibly further investigations may prove its anatomical 

 characteristics to be more permanent than we at present suppose. 



Arion hortensis, Fer. 

 var. nov. cceruieus. 



Body, blue or greyish-blue, with dark blue lateral bands, 

 and pale yellow between these and the foot fringe ; mantle, dark 

 bluish central patch, with darker bands at each side ; head and 

 tentacles, bluish-grey ; sole, variable, white or very light yellow, 

 generally covered with a red or yellowish slime ; foot-fringe, 

 white, without lineoles ; ruga, flat, large, and elongate ; 

 sulci, dark. 



Length in spirit, 27 mm. ; alive, 43 mm. 



Hab. — Co. Dublin, Ireland, and Berkshire and Oxford, 

 England. 



* I hope to deal with the variations, &c, of this species in more detail in a forthcoming 

 " Review of British Arionida." 



