296 CHASTER AND HEATHCOTE : MOLLUSCA OF OBAN. 



appearance when wet. The banded ones occur chiefly 



south and the tessellated north of Oban. The var. Jieriti- 

 formis, Bro. occurs plentifully. 

 ** Lacuna pal 1 id u la, Da Costa. A single small dead shell 



dredged. 

 L. divaricata, Fabr. Small specimens taken alive among 



Fuci on the shore and in the dredgings. 

 L. crassior, Mont. [Three dead specimens, one large, 



dredged, R.D.D. MS.]. A young dead example dredged. 

 ** Skenea planorbis, Fabr. A few taken alive under stones 



on the shore and dead in the dredgings. 

 ** Homalogyra atomus, Phil. Live and dead specimens 



occurred very sparingly in the dredgings. In some cases 



the shell exhibits strongly marked curved lines of growth. 

 ** H. rota, F. and H. Two dead specimens dredged. This 



species appears to be met with alive at but few localities. 



Mr. Robertson has taken it alive off Little Cumbrae in the 



Clyde district (Brown). 

 ** JeflFreysia diaphana. Alder. A kw live specimens in 



Lamiiiaria washings. 

 ** J. opalina, Jeff Immature specimens taken with the 



preceding, 

 * Zippora membranacea, Adams. i^Rissoamembranacea.) 



[A.M.N.]. 

 Rissoa parva. Da Costa. Abundant on Laininaria. A few 



examples of the var. interrupt a, Adams, were met with. 



This is contrary to the general rule that in northern 



localities the latter predominates. 

 R. inconspicua. Alder. [A.M.N.]. One or two dead ex- 

 amples dredged. The variety sarsii, Loven {Rissoa albella 



var. sarsii — we unhesitatingly follow Canon Norman in 



uniting albella and inconspicua — ) is common and of large 



size (4-5 mm.) on Laininaria. and occurs sparingly in the 



dredgings. 



J.C., vii., Jan. 1S94. 



