80 DISCOVERY REPORTS 



Range. Recorded also from Gauss Station, Davis Sea (Thiele, 191 2) and Burdwood Bank, 

 56 fathoms, south of Falkland Is. (Melvill & Standen, 191 2). 



Family PATELLOIDIDAE 



Genus Patelloida Quoy & Gaimard, 1834 



Type (s.d. Gray 1847): Actnaea ragosa Quoy & Gaimard = Acmaea Eschscholtz, 1833 



non Acmea Hartmann, 1821 (see Winckworth, 1934) 



Patelloida ceciliana (Orbigny) 



Patella ceciliana Orbigny, 1841, p. 482, pi. 81, figs. 4-6. 

 Patella ceciliana (Gay) Hupe, 1854, p. 260. 



Acmaea ceciliana Tryon & Pilsbry, 1891, p. 33, pi. 34, figs. 14-21. 

 Actnaea ceciliana Melvill & Standen, 1907, p. 126. 



Type locality. Falkland Is. ? 



St. 51. Off Eddystone Rock, east of Falkland Is. from 7 miles N 50 E to 7-6 miles N 63 E of Eddystone Rock, 

 4 May 1926, 105-115 m. (one dead shell). Falkland Islands (A.W.B.P. coll. Auck. Mus.). 



Range. Antofagasta to Valparaiso, Chile (Dall, 1909); Falkland Is. (Melvill & Standen, 1898, 1901, 

 1907). 



Strebel (1907) described a subspecies magellanica from Tierra del Fuego. 



Family PATELLIDAE 

 Genus Nacella Schumacher, 18 17 

 Type (s.d. Gray, 1847): Patella mytilina Helbling 

 The genus is here restricted to the thin, ovate shells with anterior apex. The thicker shelled southern 

 limpets with a bronze iridescence and subcentral apex, usually included in Nacella, are here segregated 

 into Patinigera. True Nacella lives upon the giant seaweeds, D'Urvillea and Macrocystis. 



Nacella mytilina (Helbling) 



Patella mytilina Helbling, 1779, p. 104, pi. 1, figs. 5, 6. 



Patella mytilina Gmelin, 1791, p. 3698. 



Patella conchacea Gmelin, 1791, p. 3708. 



Nacella mytiloides Schumacher, 1817, p. 179. 



Nacella mytilina Dall, 1870, p. 274. 



Nacella compressa Rochebrune & Mabille, 1889, p. 98, pi. 5, fig. 9. 



Nacella mytilina Pilsbry, 1891, p. 115, pi. 50, figs. 32-39. 



Nacella mytilina Smith, 1905, p. 336. 



Patella mytilina Strebel, 1907, p. 113, pi. 3, fig. 44; pi. 4, figs. 49, 51-55, 57, 57a, 59. 



Nacella mytilina Thiele, 191 2, p. 234. 



Nacella falklandica Preston, ?I9I3, p. 221, pi. 4, fig. 6. 



Nacella mytilina Melvill & Standen, 1914, p. 114. 



The following are probable synonyms also: Patella cymbnlaria Lamarck (1819), Strait of Magellan; 

 P. hyalina Philippi (1845) (maintained as distinct by Melvill & Standen, 1914); and P. vitrea Philippi 

 (1845) (maintained as distinct by Strebel, 1907). Preston's Nacella falklandica appears to be an in- 

 dividual variant of mytilina with strong radials. I have typical examples of mytilina from Port Stanley, 

 Falkland Islands, collected by Mr A. G. Bennett. 



Type locality. Strait of Magellan. 

 St. 222. St Martin's Cove, Hermite Island, Cape Horn, 24 April. 1927, on Macrocystis. 



