34^ BURKILL AND MARSHALL: MARINE SHELLS OF SCILLV. 



Upper Norway, or from the Atlantic coast of Ireland, with the 

 exception of one specimen about one-third the size of the rest, 

 showing the same tendency to dwarf inherent in many other 

 species of Rissoa. Besides being larger and coarser, the 

 longitudinal ribs predominate over the spirals, instead of vice 

 versa. It is a curious circumstance that several other species 

 from Scilly are unusually coarsely sculptured, viz: — R. reticu- 

 lata, R. pnndura, Trophon Jiinricatus, etc., the latter so much 

 so as to be taken at first sight for T. barvicensis. 



Three new varieties are added: — Odostoinia spiralis var. 

 coarctata^ O. pusilla var. uiinuscula, and Cerithiopsis concatenata 

 {pulchella) var. lactea. 



The following are the additions: — 

 Lima subauriculata Mont.^ — St. Mary's Sound, live. Messrs. 



Smart and Cooke have already recorded 'one or two 



valves.' 

 Lepton nitidum Turt. — St. Mary's Sound. 

 L. nitidum var. convexum Aid.— St. Mary's Sound. 

 Lucina spinifera Mont. — St. Mary's Sound. 

 Cardium minimum Phil. — Muncoy Neck, two small valves. 



Not previously found on the English coasts with the 



exception of a single valve dredged by Mr. Marshall off 



Guernsey some years ago. 

 Thracia papyracea var. villosiuscula Macg. — St. Mary's 



Sound. 

 Xylophaga dorsal is Turt. — St. Mary's Sound. 



Chiton hanleyi Bean. — St. Mary's Sound. A perfect example 



and several plates. 

 C. cancellatus Sow.— St. Mary's Sound. 

 C. iaevis Mont.— St. Mary's Sound. Several plates dredged, 



and a perfect specimen from low water found by Mr. 



Ruthven Sykes. 

 Rissoa Jeffreys! Waller.— East of St. Mary's, Menavawr, 



J.C , vi.. Apr,, iSgi. 



