the Ophidium barbatum. 445 
been mentioned by Willoughby, but without any particular 
defcription. They are very different from thofe on the Ikin of 
the Ophtdium imberhe , which are fhortly defcribed by grono- 
vius. Their pofition, as may be feen in the figure, is irre- 
gular. They are difperfed over the whole body. Their form 
is fometimes round, fometimes nearly oval. They are larger 
near the head, and in the lower part of the body ; but are hardly 
to be difiinguifhed near the tail. They adhere to the body by 
means of a particular tranfparent Ikin, which is in general 
very thin, but fomewhat thicker near the neck, and extended 
loofely over the whole head : this ikin is very eafily deftroyed', 
after which the fcales falling, the body appears fpotted (fig. 1 .), 
Thefe fcales are of the fame fort as thofe that Leeuwenhoek 
has defcribed on the eel, like thofe I have feen on the Anarrhl - 
chas lupus , the Blennius viviparus , and many other fifties, which 
are commonly thought to be without fcales. When you look at 
them with the naked eye (fig. 2.) they appear as covered with 
very fmall grains ; but viewed through a microfcope (fig. 3.) 
the middle of them appears more elevated than the margin ; and 
from the center to the margin, clofe by each other, there are 
many lines or rays, formed by fmall fcales placed one upon 
another, like tiles upon a roof, the fuperior being always the 
nearer to the center. This fort of fcales, which may be called 
umbonattf, are faftened to the body by very fmall veffeis which 
are inferred in their middle ; they are to be feen on the body 
only, not on the head nor the fins. - 
1 (hall now proceed to the anatomy of this fifti, which 
certainly comprehends fome very remarkable cir.cuxnftances, 
which, I believe, have not yet been obferved in any •other 
fpecies. When we have drawn off the Ikin there appears a thin 
membrane of a filver colour, which covers the mufcles. The 
Vol. LXXI. N n n mufcles 
