400 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [694] 
to VeraCruz. New Haven, common on oysters, living, but perhaps intro- 
duced from Virginia. New York Harbor, on oysters, (S. Smith). Fort 
Macon, North Carolina (Yarrow). Georgia (Couper). Tampa Bay, Flor- 
ida (Conrad, Jewett). Texas(Roemer). Near Vera Cruz (coll. T. Salt, in 
Yale museum). 
MODIOLARIA NIGRA Lovén. Plate XXX1, fig. 236. (p. 433.) 
Ofvers. af Kongl. Vet.-Akad., Férhandl., vol. iii, p. 187, 1846; Mérch, Naturhist. 
Bidrag, Gronland, p. 93, 1857; H. and A. Adams, Genera, vol. ii, p. 515, 1858 ; 
Gould, Invert., ed. ii, p. 190, figs. 487, 488. Modiola nigra Gray, Appendix to 
Parry’s Voyage, p. 244, 1824; Hanley, Recent Shells, p.242. Mytilus discrepans 
Stimpson, Shells of New England, p. 12, 1851 (not of European authors). 
Modiola nexa Gould, Invert., ed. i, p. 128, fig. 86 (young). 
Circumpolar: Greenland, southward to Long Island; Spitzbergen, 
southward to Great Britain and Holland; Behring’s Straits, southward 
to Okhotsk. Not uncommon and of good size in Vineyard Sound, 10 
to 15 fathoms, off Gay Head, etc.; common in Casco Bay and Bay of 
Fundy, of large size, low-water to 60 fathoms; Stonington, Connecticut, 
in stomach of cod, (Linsley). 
Fossil in the Post-Pliocene of Maine, Canada, Labrador, and Northern 
Europe. 
MODIOLARIA DISCORS Beck. 
Lovén, Ofvers. af Kong]. Vet.-Akad. FérhandL, vol. iii, p. 187, 1846 ; Gould, Invert., 
ed. ii, p. 83, figs. 489, 490. Mytilus discors Linné, Syst. Nat., ed. xii, p. 1159; 
Stimpson, Shells of New England, p. 12, (non Gould, ed.i). Mytilus diserepans 
Montagu, Test. Brit., p. 169. Modiola discrepans Lamarck, Anim. sans Vert., ed. 
ii, vol. vii, p.23; Gould, Invert., ed. i, p. 129, fig. 83.  Modiola levigata Gray, 
Appendix to Parry’s Second Voyage, p. 245. Mytilus levigatus Stimpson, Shells 
of New England, p.12. Modiolaria levigata Lovén, op. cit., p. 187, 1846; Stimp- 
son, Check-List, p. 2, 1860; this Report, p. 509. 
Circumpolar: Greenland, southward to Long Island; Finmark, 
southward to Great Britain; Behring’s Straits, athe to Pa 
Sound. Very common in Casco Bay and Bay of Fundy, low-water to 
100 fathoms; not uncommon in Massachusetts Bay; rare and local 
south of Cape Cod. Saint George’s Bank and vicinity, common, (S. I. 
Smith, Packard). Gardiner’s Bay, Long Island, rare, (S. Smith). North 
of Hebrides, in 530 fathoms, (t. Jeffreys). 
Fossil in the Post-Pliocene of Canada, Greenland, and Northern 
Europe. I am unable to separate M. levigata, as a species, from the 
ordinary New England form, usually referred to M. discors, the ditter- 
ences being due chiefly to age. The common European form of discors 
shows more differences, but is probably only a dwarf variety of the 
same species. 
MopDIOLARIA CORRUGATA Moérch. Plate XXXI, fig. 235. (p. 509.) 
Op. cit., p. 94, 1857 ; Stimpson, Check-List, Smithsonian Inst., p. 2, 1860; Gould, 
Invert., ed. ii, p. 193, fig. 491. Mytilus corrugatus Stimpson, Shells of New 
England, p. 12, 1851. Mytilus discors Gould, Invert., ed. i, p. 130, fig. 84 (non 
Linné, sp.). 
Long Island to Greenland and Northern Europe. Off Martha’s Vine- 
