DALL: MOLLUSCA AND BRACHIOPODA. 359 
Station. Locality. Depth. Bottom. Bot, temp. F. Mus. Reg. 
2890 Sta. Barbara Islands 414 sand 419.4 122814 
3354 off Panama 822 mud 469.0 122983 
3392 dics 1270 hard 369.4 122984 
3393 u i (Type) 1020 , mud 809.8 122985 
3394 A erue 511 di 419.8 122986 
3418 off Mexico 660 sand 899.0 122087 
8430 Tyr E 852 m 370.9 122988 
3431 Gulf of California 995 mud 879.8 122989 
2923 off San Diego, Cal. 822 d 899.0 110672 
This is one of the most elegant and abundant species of the region with a geo- 
graphical range of forty degrees in longitude and nearly 2000 miles in latitude. 
Dentalium brevicornu PILSBRY AND SHARP. 
Dentalium (Compressidens) brevicornu Pilsbry and Sharp, Man. Conch., 1897, 17, 
p. 126, pl. 22, figs. 53, 54, 55. 
U. 8. S. “Albatross,” station 2807, near the Galapagos Islands, in 812 fathoms, 
ooze, bottom temperature 389,4 F.; at station 2808, in 634 fathoms, sand, tem- 
perature 409 (U. 8. N. Mus. 122,809) ; and station 3431, off Mazatlan, Mexico, 
in 995 fathoms, mud, temperature 379.0. 
Very closely allied to the Atlantic D. pressum Pilsbry and Sharp, but the 
tube increases more rapidly in caliber, and is decidedly less compressed on the 
outer curve, according to Pilsbry, op. cif. 
Dentalium dalli Pırsprr AND SHARP. 
Dentalium (Rhabdus) dalli Pilsbry and Sharp, Man. Conch., 1897, 17, p. 114, pl. 21, 
fig. 46. 
U. S. 8. “ Albatross,” station 3354, Gulf of Panama, in 399 fathoms, mud, 
bottom temperature 46° F. U.S. N. Mus. 129,991. Also at station 3418, off the 
coast of Mexico, near Acapulco, in 660 fathoms, sand, bottom temperature 399 F. ; 
station 4654, off Aguja Point, Peru, in 1036 fathoms, mud, temperature 389.5 ; sta- 
tion 3346, off Tillamook, Oregon, in 786 fathoms, mud, temperature 379.3 ; station 
3200, in the western entrance to the Santa Barbara channel, California, in 965 
fathoms, mud, temperature 439.1; and northward to Bering Sea, where it occurs 
north of Unalashka in from 109 to 850 fathoms. 
Pilsbry notes that this species differs from specimens o D: pretiosum, which 
sometimes approach it very nearly in size and form, by its extreme thinness and 
fragility, beside lacking the apical striation of young D. pretiosum. 
' Bpecimens from off Acapulco reach a length of 66.0 with an oral diameter of 
4.5 mm. 
