DALL: MOLLUSCA AND BRACHIOPODA. 007 
Mopaliidae. 
PLACIPHORELLA CARPENTER. 
Placiphorella blainvillei Broprrir. 
Chiton blainvillei Broderip, P. Z. S. Lond., 1832, p. 27; Reeve, Conch. Icon., Mon. 
Chiton, pl. 3, fig, 13. 
Mopalia blainvillei Gray, P. Z. S. Lond., 1847, p. 69. 
Placiphorella blainvillei Dall, Proc. U. S. Nat. Mus., 1886, 9, pp. 210, 211; Pilsbry, 
in Tryon, Man., 1892, 14, p. 310, pl. 66, figs, 20-32, 
U.S. $. “ Albatross,” station 3368, near Cocos Island, Gulf of Panama, in 66 
fathoms, rocky bottom; U. S. N. Mus. 122,968. Original locality of the species 
Lobos de Tierra Island, Peru, on a stone from seventeen fathoms (Cuming). 
SCAPHOPODA. 
SOLENOCONCHIA. 
Dentaliidae. 
Dentalium megathyris Darr. 
Plate 19, figure 1. 
Dentalium megathyris Dall, Proc. U. S. Nat. Mus., 1889, 12, p. 293, pl. 9, fig. 1; 
Stearns, op. cit., 1898, 16, p. 424; Pilsbry, Mon. Scaphopoda, Man. Conch., 
1897, 17, p. 67, pl. 15, figs. 29, 30, 81. 
n L D * . . , B 
The following table shows the distribution of this species as far as known : 
Station, Locality. Depth. Bottom. Bottom temp. F. Mus. Reg. 
*3360 Gulf of Panama 1072 sand 869.4 122,982 
T9860] — " « 1471 ooze 309.6 122,977 
EM c « 1772 mud 850.8 122,975 
8309 « 1740 ooze 309.0 122,980 
9407 off Galapagos Ids. 885 « 870.2 122,978 
9413 « « 1360 « 869.0 122,979 
95481 Gulf of California 995 mud 370.0 122,976 
8409 « « 1421 « 379.8 122,981 
8414 off Tehuantepec 2232 « 380.5 122,074 
2788 off Chiloe Id. 1050 a 309.9 110,005 
2780 off S. W. Chile 1842 869.9 87,558 
2807 off Galapagos Ids. 812 ooze 889.4 117,830 
As in previous instances the specimens in nearly all eases were badly eroded. 
A considerable range of variation was observed in the matter of curvature, some 
being straighter than other ken in the same haul of the dredge, some thinner- 
8 straighter than others taken 5 
Shelled, in many individuals the aperture being almost absolutely circular. 
