( ) 
and an half in length Delft r/ieafure, which is the 
fame with the Rhinland. 
I cut off four pieces from this Fifh, as two from the 
Back near the Head, and two others from the Belly 
in the thick part of the Fifh, with defign to make 
my Obfervations upon them the next Day. 
Accordingly, at that time, I took a view of the 
Mu fcular Fibres both in length and breadth, and 
found that the Fibres of this great Pearch were not fo 
thick as thofe of the Cod-fjfh. Upon cutting them 
tnro lengthwife, 1 faw the Apertures of the fmall 
Veffels in fo great a number, as I could hardly have 
believ d, if 1 had not feen them. I next cut fome of 
the Fibres tranfverily, and plainly found them thin- 
ner in this Pearch, than in a middling Cod-fifb, and 
faw the fmall VefTels,that compofe the greateff part of 
the Bulk of the Fibre, lying as clofe together, as 
ever I faw them in any kind of Fifh orFleff. 
To give a better notion of thefe IVIufcular Fibres, 
and of the great number of fmall Veffels, of which they 
are cnieuy compos’d } I had, fome Weeks before, placed 
fome of them cut tranfverfiy in pieces before a Microf- 
cope, with defign to have them drawn by my Painter, 
but had been obliged to defer it, by reafon of the great 
Severity of the Weather. Thefe had been a little 
moiftned before they were placed upon the Glafs, in 
order to make them ftick to it the better • and 1 have 
caufed a fmall portion of thefe Mufcular Fibres of 
the Fifh, cut thro tranfverfiy, after they were grown 
dry, and in their fhnnking had been torn off from 
the fmall Veffels, that encompaff them, to be repre- 
sented, as at L, M , AT 0, Fig. 4. The openings of 
the fmall Veffels in thefe Fibres were diffinclly to be 
feen, but appeared in fuch great numbers, and were 
E e 2 f 0 
