The Shells are indeed, in all Refpe&s but one, 
like the My t ulus vulgar is , or common Mufcle ; 
thefe being ('mail at the Hinge-End, and having a 
broad thin Edge at the Oppofite ; whereas the for- 
mer are nearly equal at both Ends, as well as ftrait 
and fomcvvhat d ep relied s and as to the Structure 
of the Fifh of both, they are alike, tho’ with this 
Email Difference, that the Lingula of the common 
Mufcle is detached towards the Point, and that of 
the other is confin’d all along. I therefore fubmit 
it, whether either of the following Names would 
not properly exprefs it, 
Mytulus cylindroides , the cylindroid Mufcle, or 
Mytnlus Dattyliformis , the Date Mufcle. Its ex- 
ternal Form conducing much to encourage the lat- 
ter, which Mr. More has hinted at, in calling the 
Stone the Dottle , Dotting , or Dating-Stone ; for 
as to the Place of its Residence, that belongs rather ■ 
to its general natural Hiftory than its diftinguifhing 
Name. 
Doftor Lifter , and after him Monfteur D'Argenf- 
ville have drawn our Dholas with five Shells 5 but 
we have fome Reafon to fufpeft they are only Bi- 
valves; for, upon examining thofe inclofed in the 
Specimen before you, in Company, with Mr. Hill ’ 
none of them appeared to have any more than two 
Shells. And in a Specimen (given to Mr. Deter 
Collinfon by Sir Charles JVager) of one of thefe Fifh, 
which lodg'd itfelf in the Bottom of a Ship, there 
were but two Shells found ; which Shell together 
with the Piece of Wood, wherein it was lodged, I 
myfelf faw along with feveraf other Friends in the 
above - mention’d Gentleman’s Colle&ion. Now 
thefe ought, in like manner, after its generical 
Character, 
