40 DI S C O V E R Y OF THE L A C T E A L
glands through which they pafs, before they terminate in the internal jugular
veins. Nay, as often as I had a little time to fpare for the diiTeilion of the
parts, I inflated the lymphatic veiTels and glands of the neck; after which, I
handed to the ftudents thefe diffeded parts laid on plates, that fuch as chofe
might take a nearer view of them. I likewifc have conftantly, on this occafion,
handed around my preparation of the lacteals of the turtle injeded with quickfilver.
Much later, to wit, in Odober 1768, Mr Hewfon prefented to the Royal
Socicty of London an account of the lymphatic fyftcm in birds ; and m a note
added, he fays, he had fo long ago as in the winter 1763:64 obferved ladeals
in a turtle.
In a paragraph fubjoined to the above account, dated December 3. 1768, he
adds. That iince the above paper was put into the hands of the fecretary, he has
difcovered the fame fyftem in fiih ; and has likewife been fo fortunate as to procure
a turtle, whofe lymphatic fyilem he has traced out, and has got delineated.
Accordingly, in June 1769, he prefented to tlie Royal Society an account of
the lymphatic fyilem in amphibious animals and in fifhes.
Not contented with the merit of having merely profecuted the particular
branches of tlie lymphatic fyitem in fome of the oviparous animals, Mr Hewfon
thought proper to affume the title of tlieir firil difcoverer; endeavouring to
perfuade his readers, that although the paragraphs above quoted, the authenticity
of which he could not venture to call in queftion, proved that I had perfuaftons
and opinions of their exiftence; yet tliey did not prove I had in reality
difcovered them. And, to give colour to thefe pretences, he has ventured to
publifli notes which he thought fuited his purpofe, taken indeed by fome very
refpcdable ftudents who had attended my ledures.
But t]2oug]i-theie.-iLQt«s,iirejalpably erroneous as well as imperfed; and that the
principal of them, particularly the not«c.of.Pr J v l o r p n , who attended my courfeof
ledures at the fame time with Mr Hewfon, are not taken from my Ledures on
Comparative Anatomy when I accompanied my defcriptions with difTedion and
demonilration, but from a more early part of my courfe, in which, wliilil treating
of the lymphatic fyitem in the human body, I ufed to mention the lymphatic
fyftem in the oviparous animals in a curfory way only • yet even thefe, when
compared with the preceding extrads, lead to conclufions very oppofite to thofe
Mr Hewfon has drawn ; for they plainly ihow that he mifreprefented the following
very material points.
Firft, Becaufe after fummer 1761 I told the iludents that I had not obferved
coloured liquors enter the ladeal veffels of birds, he reprefents mc as acknowledging
I had never feen the ladeal veiTels; yet he knew that, for three fucceffive
years preceding that time, I had ihown collapfed bluifli veiTels in the mefentcry
of fowls, different from the branches of the mefenteric artery and vein.
He faw mc demonilrate thefe in the winter 1761-2; and he muft afterwards have
certainly
AND L Y M P H A T I C VESSELS. 4«
ccrtainly known, as I tlid, that the veiTels I then, and every year fmce, pointed
out, were t/i reality the ladeals of fowls. Nay, before he publiilied, lie himfelf
had found by experiment, that the chyle in the ladeals of fowls was always colourlefs;
and therefore he knew, that my not feeing coloured chyle was no proof
that the velTels I had feen were not the ladeals.
Secondly, Mr Hewfon, upon the credit of what he knew or might have
known to be in Dr Morgan's notes, has afcribed to Mr John Hunter a difcovery
of mine in 1760 ; which,. fo far as I know, that gentleman never afTumed, and
from which the exiilence of the valvular lymphatic fyftem in birds was proved,
to any perfon who undcrftands the fubjed, beyond all poiCbiUty of doubt or deception:
I mean my having, in 1760, firil difcovered conglobate glands at the
Jower part of the neck of fowls fimilar to our gland ulze vagas, and having inflated
valvular lymphatic veflels entering thefe at their upper, and coming out at
their lower part, to terminate in the internal jugular veins.
Mr Hcwfon's arguments, by which he pretended to fiiow tliat I had not anticipated
him in the difcovery of the ladeals in fiflrcs, are equally unfortunate.
That the reader may not think I mifreprefent them, I iliall fl:ate'thcm in his
own words. " Next (fays he) as to the ladeals in fiih. To prove that he (Dr
Monro) had found thofe veiTels eight years ago, he (Dr Monro) tells us, that in
a note taken from the diiTeclion of a flcate on April 24th 1760, he has faid,
' He had difcovered a whole fyfl:em of 'ladeals and lympharic veiTels, running
' towards the heart, on tlie left of and above the vena portarum; and from
' thefe the auricle of the heart was blown up. They are proportionally larger,
' but have fewer valves than in man.'
" Now (continues Mr Hewfon), I will take upon me to fay, there is noticing
in this note which proves whether he had inflated a ladeal or a vein: For what
he fays of the fituation of the veiTels, and of his blowing up the .heart, is equivocal.
The only part of the note wliich appears to chai-aderife the Isdeals is in
reality a miftake; that is, where he fays tJi-.)' /lavc valves."
In anfwer to all this, I would obfcrve two plain fads. The firfl: of wliich is,
that tire red veins of the mefentery in fiflies, .as well as in man, do not lead to
the heart, but to the vena portarum. When tlierefore I found that the veiTels
I inflated led diredly to tlae heart, I knew them to be for certain the lactcals.
In the next place, the veflels I inflated were in their appearance totally difl^ercnt
from the red veins. They formed a great plexus, or what I have called
" a whole fyflcm of ladeals and lymphatics running towards the heart; were
" larger, and appeared to have fewer valves than in man." But Mr Hewfon
exclaims they have no valves ; and therefore would infer that I had not feen
their ladeals. But fuppoflng they had no valves, it would by no means follow
that I had not inflated their ladeals; becaufe they are in reality not cylindrical
vcfl'els, but arc jointed ; and of courfe I judged, from the analogy of the human
body, that they were valvular.
Further, it has appeared, that within the ladeals of the ikate there are cellu-
L lar
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