Marine Shells of. Massachusetts. 265 
B. trivittàtum. Nassa trivittata, Sav, Journ. Ac. Nat. 
Sc. II. 231 — 
At New Bedford fair specimens of this. shell are not 
abundant. After a violent storm, however, I have found 
them living. At Nantucket this species is abundant. 
Last May, being upon the inner side of Brant point, I 
found great numbers a few rods east of the ship yard, 
but a little below high-water mark, burrowing i in the 
clean siliceous sand. Furrows, several feet long, of the 
width of the shell, had been made by the crawling of 
the animal. In the act of burrowing, the base of the 
shell was downward, but when the animal was at re- 
pose in his burrow, the position was completely inverted. 
On the south shore of Nantucket, I have found them - 
of a larger size, but not living and not abundant.  . 
— . Say's description applies well to the shells from these 
localities, except that of the three lines of rufous color 
upon the body whorl, that next the suture is darker. 
The shade of the lower line or band deepens next 
the outer margin. It should be added, that the two 
upper bands of rufous color are double, being upon 
each side of one of the revolving impressed lines, 
and that the lower one is sometimes triple. But these 
bands are often nearly or quite obsolete, or confluent 
upon the entire surface, in the specimens from Brant 
point. The live shell from this locality, although in 
clean sand, is covered with a dirty cinereous pigment. Li 
- Length of one of the live shells from Brant point 
ge; breadth .35 inch ; length of a dead shell from 
the south shore o of amok .85 inch ; yen 40 
| of an inch. 
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