ANACHIS. 161 



and evenly rounded ; suture somewhat impressed, but not deep, 

 frequently narrowly channeled ; surface, except anteriorly and 

 on the canal, destitute of spiral lines, and of any indication of 

 ribs, but covered with very close, almost microscopic lines of 

 growth, which give the surface a dull appearance when dry ; on 

 the canal and extending to the anterior part of the body-whorl 

 are a number of distinct spiral lines becoming faint opposite the 

 middle of the aperture; fine, microscopic spiral striations some- 

 times appear on the lower whorls. The nucleus is larger than in 

 A. rosacea, rounded, depressed and spiral, but somewhat mammil- 

 lary. The aperture is small, oblong-ovate ; the outer lip is sharp 

 at the edge, but in adult shells has a distinct thickening a little 

 back from its margin ; the inner surface is usually smooth, but 

 in some adult specimens there are four. or five small, ti'ansversely 

 oblong tubercles, back from the margin, and a larger conical 

 tubercle at the base of the canal. Columella sigmoid, a little 

 excavated in the middle, and with a distinct, raised, spiral fold 

 at its inner edge, anteriorly ; canal short, open, very slightly 

 curved ; epidermis thin, closely adherent, minutely lamellose 

 along the lines of growth, pale greenish gray, or yellowish white. 

 Length of one of the largest specimens, 12 mm., breadth 4 mm., 

 length of aperture, 5 mm., its breadth 1"8 mm. Stouter and 

 shorter examples occur. 



Off Martha' s Vineyard, in 65 to 487 fathoms, 1880 and 



1881 (U. S. Fish Commission). Off Chesapeake Bay, 

 300 fathoms ^Capt. Tanner). Taken at many stations. 



This species resembles G. rosacea, of which I formerly sup- 

 posed it to be a deep-water variety. A more careful examination 

 of a larger and better series convinces me that they are distinct. 

 The present species is a more slender and elongated, and far 

 more delicate shell, and is destitute of the impressed spiral lines 

 that cover the whorls, both in that species and G. Holbollii, and 

 is without any traces of transverse ribs, on the upper whorls. 

 The fold on the columella edge and the submarginal thickening 

 of the outer lip are also good distinctive marks, but the gi-eat 

 difference in the nucleus is, perhaps, of still greater importance. 

 Fresh specimens, when wet, are so transparent that the internal 

 form of the columella can often be seen through the shell. 



The above is Prof. Yerrill's description in full. 

 21 



