N0.1237. SYNOPSIS OF THE LUCINACEA—DALL. 793 



U. rubra Roissy ^ and the earlier ctmeata of Spenglev. Con rad ^ reported 

 the presence of this species in a mass of coral rock containing- many 

 West Indian boring molkisks, but this discover}' has not been contirmed 

 by any subsequent collector or explorer, though in itself not inher- 

 ently improbable. In the absence of confirmatory evidence we can 

 not regard the presence of Ihujulinacuneata in the American or West 

 Indian fauna as sufficiently established. 



No species of Felanla in the correct sense, or of Joannisiella, are 

 known from the Western Hemisphere. 



LIST OF EAST AMERICAN SPECIES. 

 DIPLODONTA TORELLI Jeffreys, 1876. 



North Atlantic, southeast of Greenland, in 1,450 fathoms. Spits- 

 bergen, in moderate depths of water. Also Aleutian Islands. 



A rude, chalky species of large size, which may perhaps be found 

 later on the Labrador coast. The figure of Lucina leucophceata Reeve, 

 1850, somewhat resembles this species. 



DIPLODONTA PUNCTATA Say, 1822. 



Cape Hatteras, North Carolina, to Rio de Janeiro, Brazil, in 14 to 

 124 fathoms, southward to the Straits of Magellan, and thence north 

 to Chiloe Island. 



This is Aitiphldesnia jyimctata Sa}', 1822; LncJna (juaraniana d'Or- 

 bigny, 1846; Lucina venezuelensis Dunker, 1848; Z. janeirensis Reeve, 

 1850; L. suhglohosa C. B. Adams (1847), 1852; L. hrasiliensh Mittre, 

 1850 (but not L. hrasiliana d'Orbignv, 1846, or IrrasiUensis Philippi, 

 1850); Diplodonta Philllppll Huppe, 1854, and Mysia pellucidalA&\- 

 prin, 1889. 



This is a phiin, globose shell, with feeble incremental sculpture and 

 microscopic radial stride. The anterior end is somewhat attenuated 

 and the posterior expanded. The young are often nearly orbicular. 

 The specific name is derived from the punctation visible on the disk, 

 internally in many specimens. It appears to pass through Magellan 

 Strait and reach as far north as the island of Chiloe, on the Pacific side 

 of South America. 



DIPLODONTA NUCLEIFORMIS Wagner, 1838. 



Cape Hatteras, North Carolina, to Porto Rico and St. Thomas, 

 West Indies, in 15 to 52 fathoms. 



This is My><la nvcleifoniiis of Wagner; Loripes elevata Conrad, 1845; 

 Cytherea sphcerica H. C. Lea, 1845; Diplodonta elevata Conrad, 1858, 

 and JfysHi carolinensts Conrad, 1875. 



It is a small, suborbicular, globose species, which goes back to the 

 Oligocene in time. 



iSonnini's Buffon, Moll. VI, 1805, p. 575, pi. lxvi, fig. 4. 

 ■^Amer. Jour. Sci. XXIII, no. 2, 1833, p. 345. 



