inhabiting the seas of Great Britain and Ireland. 337 



Differs from the last species (to which it is allied) in form and 

 textm'e, in the whorls being more rounded and the suture more 

 distinct, and especially in the regular impressed concentric strise. 



Zetland, five miles east of Lerwick, in forty fathoms water, where 

 one specimen only occurred to me. 



3. Odostomia Rissoides. 



Odostomia scalaris, Macg. Moll. Ab. 154. 



Odostomia Rissoides, Hanley in Zool. Proc. 1844; Thorpe, 36. 

 fig. 9. 



Aberdeen (Macgillivray). Guernsey (Hanley and Mr. Barlee). 

 Caswell and Langland Bays near Swansea ; Tenby ; Fishguard ; 

 Whitesand Bay, Cornwall ; Scarborough. Exmouth (Mr. Clark). 

 Roundstone and Arran Isle, co. Galway (Mr. Barlee). 



Var. a. scalariformis. 

 Burrow Island, Devonshire (Mr. Barlee). 



Var. b. plus ovalis et anfractu ultimo majore. 

 Aberdeen (Mr. Macgillivray). 



The specific name of scalaris was preoccupied by Philippi at 

 the time of Professor Macgillivray^ s publication, although the 

 last-named author is perhaps entitled to priority in distinguish- 

 ing the species. 



A local species. 



4. Odostomia alba. 



Testa oblongo-ovata, tenuis, nitida, glabra, alba ; anfractus 

 5-6, ventricosi, sensim increscentes, ultimo reliquos cxsuperante ; 

 apex subacutus ; sutura profunda ; apertura magna, rotundata et 

 subtus vix effusa ; umbilicus valde conspicuus ; denticulus par- 

 vus, columella subobtectus. Long. -^, lat. yg unc. 



Somewhat resembles Rissoides, but the whorls are more swollen 

 and tapering. The umbilicus also is a very distinct character, 

 there being none in the other species. 



Oxwich Bay near Swansea. 



Var. a. paullo major et plus conica. 

 Bantry Bay (Mr. MacAndrew). 

 A rare species. 



5. Odostomia nitida. 



Odostomia nitida, Alder in Ann. Nat. Hist. (1844), p. 326. pi. 8. 

 fig. 5 ; Id. Cat. 52. 



Tynemouth (Mr. Alder). West coast of Scotland (Mr. Barlee). 

 Torquay (Dr. Battersby). 



Var. a. paullo major, ad basim subcarinata et latior. 

 West coast of Scotland (Mr. Barlee). 



