88 JOURNAL OF CONCHOLOGY, VOL. 15, NO. 3, JULY, I916. 



R. striata A. Ad. — The Rev. R. Boog Watson has noticed that 

 the surface of this shell is covered by a " delicate microscopic spiral 

 fretting," similar to that which adorns R. a'cdonis Wats. 



var. aculeus Gould. — From a raised beach in Skye (Scott) ! 



R. proxima Aid. — Clyde, 2of. ; Davar Island, 2 6f. ; Sanda Island, 

 25f. ; and Mull of Cantire, 55f. (Knight)! Achil Island; off Loch 

 Ryan, 25-2Sf. ; ten miles south of Arran, 6of. Most of the Hebridean 

 specimens belong to a small and slender form. 



R. vitrea Mont. — Clyde mouth, 2of. ; off Loch Ryan, 25f. 



R. pulcherrima Jeff. — Alderney (Marquand) ! 



var. pellucida Marsh. — R. amabilis Monts. does not appear to 

 me distinct from this variety. The former is a more slender form of 

 the type, with the whorls more convex, and is found occasionally in 

 the Channel Islands. Jeffreys' figure well represents this form in 

 outline. 



R. fulgida Ad. — Skipness, at the mouth of Loch Fyne, living in 

 corallines (Somerville) ! off Loch Ryan, 27f, two dead specimens. 



R. obtusa Cant. — Some specimens from the Adventure Bank, 

 dredged in the ' Porcupine ' Expedition, are regularly ribbed with 

 longitudinal lines of growth, in the same manner as I have related of 

 Odostojnia acicula from the same locality.^ Another extreme form is 

 more conical, approaching in outline R. triangularis Watson, a minute 

 shell, by the way, that must have puzzled Gwyn Jeffreys, as he de- 

 scribed it in the ' Porcupine ' Report as a Trochus {minutulus), but 

 from an examination of specimens, figures, and text, I am satisfied 

 they are one and the same species. 



R. semistriata IMont. — Mull of Cantire, igf. 



var. pura Jeff. — Benbecula. A specimen from the Mediter- 

 ranean has longitudinal riblets, which dominate the spiral strije. R. 

 galvagni of Aradas is the dwarf form of this species. 



R. cingillus Mont. — Benbecula. Two specimens from Alderney, 

 collected by Mr. Marquand, are of a uniform dark purple, without 

 bands. 



Hydrobia Hartm. — One of the recommendations of the Inter- 

 national Zoological Congress — an authority which, if any, is the most 

 likely to endure, and at any rate one which cannot be ignored — laid 

 down that it was "well to avoid the introduction of new generic 

 names which differ from those already in use only in termination, or 

 in a slight variation in spelling, which may lead to confusion ; but, 

 when once introduced, such names are not to be rejected on this 

 account." 



I Jouni. of Conch. ^ 1900, vol. ix., p. 336. 



