DALL: MOLLUSCA AND BRACHIOPODA. 277 
Smaller, more slender, and with a distinctly more excavated fasciole than in 
the last species which also has the keel usually nodulous. In the better pre- 
Served specimens the spiral sculpture is continued in front of the keel while 
M the two preceding species it is confined to the anal fasciole. 
Borsonia (Borsonella) saccoi Dart, n. sp. 
Shell much eroded, solid, short, chalky, with an olive-gray periostracum and 
Over five whorls; spire short, conic, nuclear whorls lost; the anal fasciole de- 
pressed, forming a constrieted concave band near the posterior edge of the whorl 
Which is thickened and marginate ; on the anterior side of the fasciole the shoulder 
9f the whorl forms the periphery on which are (thirteen on the last whorl) short, 
Tounded, wavelike nodules or axial ribs which are slightly protraetive and do not 
extend over the base; the other axial sculpture is composed of rather marked 
elevated, more or less irregular lines of growth; on the fasciole and base these 
are more or less obscured by spiral impressed lines with much wider interspaces, 
Which appear feeble and as if obsolete where not eroded ; canal short, straight; 
Outer lip simple with the sulcus near the suture, rather wide and deep when com- 
plete ; body with a white callus and near the insertion of the pillar a single very 
strong sharp edged spiral plication extending into the spire. Lon. of (eroded) 
shell, about 14; of aperture, about 7 mm. ; max. diam. about 7 mm. 
US, 8, “ Albatross,” station 3354, Gulf of Panama, in 399 fathoms, mud, 
bottom temperature 409 F, U.S. N. Mus., 193,105. 
Although this specimen is so imperfect it is clearly distinct from any other col- 
ected in the region and is therefore worthy of description. It differs from the 
others in its stronger ridge in front of the suture, its fewer, longer, and more per- 
‘stent ribs. The plication on the pillar extends fully to the columellar callus, and 
55 quite conspicuous. 
Borsonia (Borsonella) coronadoi Daz, n. 8p. 
Plate 14, figure 2. 
Shell slender, acute, pinkish white, with a pale brown periostraeum and about 
en whorls; spire longer than the aperture, the nuclear whorls smooth, turgid, 
the Subsequent turns carrying a rounded low keel, usually in front of the middle 
of the whorls forming the spire, the area between which and the suture is flatly 
Impressed, the whorl in front gently rounded ; on some of the early whorls the 
eel is slightly undulated, but not regularly nodulous ; besides the lines of growth, 
oth the fasciole and the anterior part of the whorl show indications under a lens 
of obscure regular distant spiral striae, and are also more or less marked with a 
faint vermicular reticulation of the surface; suture not appressed, distinct; aper- 
Ure narrow, anal sulcus deep and wide, reaching the suture; outer lip thin, 
sharp, arcuately produced; inner lip slightly eroded, polished, with no callus; 
