JOURNAL OF CONCHOLOOY, VOL. 15, NO. 9, MAY 1ST, I918. 261 



Stelfox cannot recognise it is no proof that it is not a well-marked 

 form, and further research may not impossibly cause him to change 

 his views, especially if, distrusting the unaided eye, he will make use 

 of the microscope, without which instrument no work in this difficult 

 and puzzling group is possible. 



" Superficial views " are notoriously fallacious, and have been the 

 cause of all the confusion in the study of this group in the past. 

 "It looks like" is not sufficient to-day unless supplemented by a 

 careful microscopical examination of the hinge characters. 



Complaint has also reached me, from various sources, that some of 

 my past determinations, on comparison, will not always agree with 

 later ones. It would be surprising if they did. So soon as it became 

 known that I was working at the group, and before I had been able 

 really to settle the various forms, my aid in determining specimens 

 was invoked, and with more wishfulness to oblige than, perhaps, 

 wisdom, I complied. Many hours did I devote to various gatlierings 

 received from different correspondents ; but, naturally, many of these 

 early determinations have proved to need revision. Papal infalli- 

 bility was never claimed for them, and many correspondents have 

 courteously, when in doubt, referred such doubtful cases back to me. 



Otina Otis Turtonat St. Mary's, Scilly. — Looking over the catalogue^ of 

 Scilly Islands Marine Mollusca collected a good many years ago by the Revds. 

 R. W. J. Smart and A. H. Cooke, I noted but one locality given for the interesting 

 little species Otina otis Turt., viz. : " Piper's Hole, Tresco I." This is a cavernous 

 recess, somewhat after the fashion of the famous Gouliot Cavern, Sark. Although 

 it is now almost fifty-one years since I visited the Scilly Isles, in company with my 

 friend, the late Mr. Jonathan Rashleigh, of Menabilly, Cornwall, I still have a clear 

 memory of the abundant collecting of this local species on rocks left bare by the 

 receding tide off that part of the shore of St. Mary's just north of High Town, 

 which I believe would be included in "Porlhloo Bay." The Island of Tresco, 

 where is situate the domain of the Lord of the Scillies (Mr. T. A. Smith-Dorrien- 

 Smith), with its wonderful tropical gardens and ruined abbey, is about a mile and 

 a half from this spot. I collected all round Tresco in 1866, but found no sign of the 

 Otina there. It was everywhere in Porthloo Bay, associated with huge Patellcc, 

 Balani, Mytili {j]I. edulis var. ungulaltis) and Lasaa rubra Mont. Here Otina 

 otis might be reckoned in hundreds, the Lasa-a in countless thousands. I never 

 saw these last so abundant elsewhere, the var. pallida occurring more rarely. 

 Alexia bidentata Mont, was likewise present. In Smart and Cooke's list Lasaa 

 rubra is only mentioned as occurring at "Golden Bell Bar," and its variety "on 

 rocks under Connell's Castle." As these enthusiastic collectors only found Otina at 

 the "Piper's Hole" locality, to quote their own words, "after many days' search- 

 ing along the rocks, thus being at last rewarded," I think this short note may merit 

 publication. I may add that on the grassy margin of this bay, the curious pink- 

 flowered Townsend's Trefoil ( Trifoliutn repens L. var. Townsendi) was abundant, 

 and I found two specimens of the rare beetle Gnorinius nobilis on its flowers. — 

 J. Cosmo Melvill {Read before the Society, May 9th, 1917). 



I Journ. 0/ Conch., iv., p. 301, 1SS5. 



