IREDALE : ON NAMES OF BRITISH MARINE JIOLLUSCA. 331 



(ex Klein) in place of Gray's name Patina, over which it has eight 

 years priority. 



DiODORA, Gray. 



In the List Fissurella grceca appears. The species grmca cannot 

 be referred to the genus Fissurella, so that error is here at once 

 apparent. Fissurella was introduced by Eruguiere in the Encj^cl. 

 Method. Vers., vol. i, p. xiv, 1791, with a vague diagnosis, and no 

 species cited. At this introduction it can only be considered a nomen 

 nudum. In 1799 Lamarck in the Mem. Soc. Hist. Nat., p. 78, 

 cited in conjunction the species Patella nimbosa, Linne. The name 

 then dates for actual usage from this place, and nimbosa is not 

 congeneric with ^/vem. In the Man. Conch., vol. xii, p. 205, 1890, 

 Pilsbry recognized this, and allotted the species '■ grceca'' to Gli/phis, 

 Carpenter. This name was proposed in the Cat. ^Tazatlan Shells, 

 p. 220, 1856, apparently for the grceca group, but the name chosen 

 was preoccupied by Glyphis, Agassiz (Poiss. fuss., vol. iii, p. 241, 

 1843). Hedley, following Pilsbry and Johnson (Nautilus, vol, v, 

 p. 104, January, 1882), in his Cat. Marine Moll. Queensl. (Proc. Austr. 

 Assoc. Adv. Science, Brisbane, 1908, p. 352, 1909) therefore rejected 

 Glypliis, and used for a large group Fissuridea. This name was 

 proposed by Swainson (Treatise Malac, p. 356, 1840) with the 

 diagnosis "Sub-conical, cap-shaped; the summit close to the posterior 

 margin : the perforation narrow. T. pileus, Sw. Sp. nov." The 

 species was recognized as ' galeata, Helbling' by Pilsbry, and 

 Swainson's name was used for this alone. With doubt I have 

 followed Hedley in associating shells of ^ grceca^ affinity with those 

 like ' galeata, Helbling '. Kecently my doubts have been confirmed, 

 and I will later show that these two are certainly generically distinct. 

 Consequently F'issuridea is not available for the former. Dall in the 

 Proc. U.S. Nat. Mus., vol. xlviii, pp. 437-40, January 19, 1915, 

 has discussed the names given to species of this family in the 

 Conchological Illustrations. He has there put forward Lucapina, as 

 of Sowerby, 1835, as applicable to the group. On his data I would 

 prefer Foraminella, but we are saved from a further complication by 

 the recognition of a name long anterior to Lucapina or Fissuridea. 

 Gray in the London Medical Repository, vol. xv, p. 233, March 1, 

 1821, proposed Diodora for Patvlla apertura, Mont. It is acknow- 

 ledged, without argument, that Patella apertura was based upon the 

 immature stage of the British shell known as Fissurella grceca. This 

 name, then, is available, and must be used for the grceca affinity. 

 The laws governing zoological nomenclature are definite on this point, 

 and the subject requires no discussion. It is obvious that this detail 

 was simply overlooked by Pilsbry and Dall, as neither of these workers 

 would consider any argument with regard to such a simple matter. 



The correct specific name of the British shell may as well be here 

 discussed. Though 'grceca' was used in the List, this Avas against 

 the conclusions of most conchological writers. The majority have 

 affirmed the distinction between the British shell and the Mediterranean 

 one named ^ grceca\ Owing to confusion the majorit}' of workers on 



