COMPLETE GRAU: PECTINIDAE OF THE EASTERN PACIFIC 125 



Semipallium (Juxtamusium) natans (Philippi) 1845 



Plate 42, figs, 1-2 



Pecten vitreus King, 1831, p. 337. "Habitat in Freto Magellanico 



(passim)." 

 [non] Ostrea vitrea Gmelin, 1791, p, 3328. "Habitat in Oceano sep- 



tentrionali." ["Northern ocean."] 

 Pecten corneus G. B. Sowerby, 1842, p. 71, pi. 13, figs. 44, 45; pi. 20, 



figs. 244, 245. "Magellan." 

 [??o/z] Pecten corneus J. Sowerby, 1818, p. 1, tab. 204. Fossil species. 

 Pecten natans Philippi, 1845, p. 57. "Patria: Fretum Magellanicum, 



Messier-Canal, Smith-Canal." 

 Pecten nasans [lapsus calami] Philippi. Reeve, 1853, sp. 113, pi. 27, 



fig. 113. "Straits of Magalhaens." 

 Pecten Jeffrey si de Gregorio, 1884b, p. 133, New name for P. corneus 



G. B. Sowerby. 

 Pseudamussiutn nasans A, Adams, Mabille & Rochebrune, 1891, p, 



H-126, "Baie Orange." [Orange Bay, Tierra del Fuego.] 

 Pseudamussiutn corneum A, Adams. Mabille & Rochebrune, 1891, p. 



H-126. "Detroit de Magellan." 

 Pseudamussium nasans Philippi, Dautzenberg, 1896, p, 65. 

 [?] Pecten Thomasi G. B, Sowerby, 1897, p, 138, pi. 11, fig. 2. Locality 



unknown to Sowerby, "= P. corneus adult," fide Melvill & Sykes, 



1898, p, 46; =P. corneus G. B. Sowerby, fide Bavay, 1905, p. 29. 



Synonymy dubious; one reason: maximum height of natans ( = 



corneus) about 35 mm, holotype of Thomasi (only specimen 



known) 65 mm. 

 Chlamys cornea G. B. Sowerby. Bavay, 1936, p, 307. In synonymy: 



^^ natans Philippi, Thomasi Sowerby." Footnote: "Reeve a deforme 



ce nom en nasans." 

 Pecten natans Philippi. Carcelles, 1950, p, 76. "Sur de Patagonica y 



Region magallanica." 

 Holotype: ? 



Type locality : Strait of Magellan. 



Original description : P. testa subaequivalvi, subaequilatera, ovata- 

 orbiculari; costis planatis, in junioribus 25, in adultis circa 50, alternis 

 minoribus ; costis interstitiisque laevibus. 



var, a) minor, tenuissima pellucida, 15'" alta, 13^'" lata, 4^'" 

 crassa. 



