130 JOURNAL OF CONCHOLOGY, VOL. 9, NO. 5, JANUARY, 1899. 



ribbed ; very abundant at Guernsey and Stilly, and occasionally met 

 with in other places. The latter form is well figured by Sars as R. 

 inconspicua var. ; it is also well figured in Sowerby's "Index" as R. 

 inconspicua var. maculata Brown ; but Brown's shell is sculptured, has 

 a labial rib, and answers to the second form according to his descrip- 

 tion ; his figures are no guide. " British Mollusca " gives five 

 figures to represent the species, all good ones. 



Jeffreys has observed in the ' Lightning' Report that "the sculpture 

 is excessively variable, as regards not only the number and compara- 

 tive strength of the longitudinal and spiral strise, but even of their 

 existence." Many specimens are conical, having a shorter spire and 

 broader base. 



R. albella Lov. — Jersey ; Guernsey ; Torbay ; Exmouth ; Tenby ; 

 Milford Haven; Bantry Bay; Connemara ; Killala Bay; Iona ; Oban; 

 Loch Linnhe ; Thurso ; Barra. 



Var. sarsi Lov. — Jersey; Torquay; Exmouth; Skye ; Barra. 

 Narrower. 



Common in all the estuarine deposits of north-east Ireland, both 

 type and var. sarsi (Praeger) ! 



Jeffreys is not so clear as usual in defining the characters of R. 

 albella and its var. sarsi. He says the type has "usually a few minute 

 spirals," but " sometimes also longitudinal ribs," while he figures it 

 (as do Forbes and Hanley) as a ribbed shell. He then states that 

 " the labial rib rarely occurs on smooth specimens," whereas the 

 majority of specimens of the type are smooth and invariably have a 

 labial rib. In the 'Lightning' Report he complicates matters by say- 

 ing that " the principal difference between R. albella and R. sarsi 

 consists in the latter having more convex whorls and consequently a 

 deeper suture"; but it is the type that is the tumid form and has the 

 deeper suture, as may be seen on reference to his figures. Finally, 

 he gives the habitat as " Bantry Bay at low water," implying that that 

 is its only British habitat; but it is pretty widely diffused, as my 

 records above will show, and is rather common in some places, the 

 majority, however, being ribless, though always having the labial rib. 

 I think Dr. Jeffreys could not have been so well acquainted with this 

 species as he undoubtedly was with the other members of this genus. 



Next to R. parva, it is the most variable of all the Rissoce, and most 

 collectors have found some difficulty in separating it from R. incon- 

 spicua. Some specimens certainly run close to R. inconspicua, espe- 

 cially a small form of it which has the same length and breadth ; but 

 the latter is always more conical, with a longer spire and sharper apex. 

 It is emphatically a species not to be pronounced upon off-hand, 

 and it is, moreover, one essentially requiring the critical faculty and 



