MOLLUSCA.—HEDLEY. 
25 
Gaimardia trapezina Lamarck, 
var. coccinea var. nov. 
(Plate II., figs. 20, 21, 22.) 
Modiola trapesina Lamarck, An. s. Vert., vi., 1819, p. 114 ; Id., Delessert, Recueik, 
1841, pi. xiii., fig. 7. 
Gaimardia. trapesina Gonld, Am. Expl. Exped., xii., Moll., 1852, p. 459, pi. xli., fig. 568. 
Phaseolicama trapezina Hupe, Hist. Chile, Zook, viii., 1854, p. 323, pi. viii., fig. 9. 
Modiolarca trapezina H. and A. Adams, Gen. Rec. Moll., ii., 1857, p. 520, pi. cxxii., 
fig. 1 ; Id., Chenu, Man. de Conch., ii., 1862, p. 156, figs. 777-9 ; Id., Smith, 
Phil. Trans. Vol., 168, 1879, p. 190, and Chalk Rep. Zook, xiii., 1885, p. 279 ; 
Id., Martens and Pfefier, Jahrb. Hamburg Wiss. Anst., iii., 1887, p. 127, pk iv., 
fig. 13 ; Id., (+ M. crassa + M. cannellieri + M. lephayi + M. savatieri + M. 
fuegiensis + M. hahni, all of M. & R., fide Stempell), Rochebrune and Mabille, 
Miss. Scient. Cap Horn, 1889, Moll., pp. 120-123, pk vii., figs. 1, 2, 3, 4, 5, 6, 7 ; 
Id., Smith, Proc. Malac. Soc., iii., 1898, p. 24 ; Id., Melvill and Standen, Journ. 
of Conch., ix., 1898, p. 104, and x., 1901, p. 47 ; Id., Stempell, Zook Jahrb. 
Supph, iv., 1899, p. 327 ; Id., Pelseneer, Voy. “ Belgica,” Moll., 1903, p. 11 ; 
Id., Lamy, Ann. Inst. Oceanograph, iii., 1911, p. 44; Id., Thiele, Deutsch. 
Siidpol. Exped., xiii., 1912, p. 252 ; Id., Suter, Man. N.Z. Moll., 1913, p. 896, 
pk lxiii., fig. 6 ; Id., Lamy, Bulk Mus. Hist. Nat., xxi., 1915, p. 75. 
Gaimardia trapezina Iredale, Trans. N.Z. Inst., xlviii., (1914) 1915, p. 487. 
At Macquarie Island, this is abundant. Mr. A. Hamilton writes *—“ The most 
attractive shell is a bright scarlet bivalve which attaches itself to the bright green Ulva 
in the rock pools and to the kelp in the deeper water, it is very plentiful.” 
According to Mr. E. A. Smith, it has a wide circumantarctic range, from Patagonia, 
the Falkland Islands, South Georgia, and Kerguelen to Macquarie Island. The eight 
forms, separated by Mabille and Rochebrune but united by Stempell, speak for the 
variability of the species. A large series from Macquarie are constant in form and 
colour, and, judging from literature, so differ from South American representatives 
as to be worth, at least, varietal distinction. Accordingly, it is now proposed to term 
it var. coccinea. All the Macquarie Island shells are uniform vermilion outside and 
peach-blossom pink within. South American specimens are described as yellow and 
brown. The largest of 300 Macquarie shells is only 19mm. long, whereas Lamarck’s 
type is 22mm. and Modiolarca crassa is 32mm. long. The drawings of Delessert and 
Gould show a form much longer in proportion to height. And if Chenu’s figure is to be 
trusted the hinge of Lamarck’s species differs from that of the Macquarie Island shell. 
* Hamilton.—Trans. N.Z. Inst., xxvii., 1894 (1895), p. 577. 
Vol. iv., Part 1 — d 
