48
ME. R. H. BURNE ON THE AOBTlU-ARCH
PLATE
IV.
Fig. 9. Section of the free edges of two lamella: of the lung-book.
10. Section through lamellre of lung-book near their base.
11. Part of the wall of the air-space towards the centre.
12. Section of wall of air-space towards the side.
13. Side view of mouth and surrounding parts. The left first and second
appendages have been removcd and the thorax laid open. i. and ii.,
right first and second appendages ; cur., carapace ; qs., epistome;
m.,mouth : p.s.t., sense-orgm on base of appendage ii.
12. Ventral sclerites of second and third free segments, viewed from
inside.
15. Sectaimof wall of stercoral pocket.
10. Section of one of the Malpigliian tubes.
17. Section of epithelium of proctodmim.
PLATE
V.
Fig. 18. Ventral surface of abdomen of Phr:ynus reniformis, with egg-sac.
19. Young embryo of Phryaws rwl:fbrmis : stirface view.
20. Side view of embryo of Phny~iissanmskatipas. x 9. Lo., lateral organ.
21. Sclieinatic longit,udinal vertical section of Phry77u.9 aiznuZat~'pes,
x . '$
ox., median eye; gem^, genital aperture ; Stc., stercoral pocket ;
Pr., proctodzum.
29. Longit.ndina1 section of first four abdominal segments. x ".
23. Longitudinal section through front part of coxal gland and duct.
On the Aortic-Arch System of Saccobralzchusfossilis. By R. H.
BERRP,
B.B. Oxoii., Assistant in Museum, Royal College of
SLirgeons, London. (Communicated by Prof. G. B. HOWES,
F.L.S.)
[Read 6th April, 1894.7
IN tropical countries, b u t
more especially in India, where the
streams and tanks are liable to become dry in the hot season, a
number of the freshwater fishes have acquired the power of
living for a longer or shorter time out of water, and are t h u s
enabled either t o migrate t o places r h e r e water is more abundant,
or t o bury themselves deep down in the mud t o await the revivifying rains. Many years ago * reports that fish were often
dug up in spots that had been dry for months, or were found
* F o r the early literature of this subject see Boake, Journ. Ceylon Branch
Asiat. SOC.1865, and Day, Proc. Zool. SOC.1868, p. 274.
s T s'r I,:JI
()
F
s .i c c ~II )11.1 xc 11 I's I;0 s s I L I S .
-&!)
watidc~ringfkr from any water, st,irrcd tlic curiosity of iiaLiu.aIi.sts,
atid fi nally led t o the reeugiiitioii, na accessory respiratory c i r g ~ i s ,
o f certain structural modilicntioiis octcurriiig i i i these tislies.
~i or some time t h e e m c t trietliucl by wliicli this respirntioii w a s
-1
cffectecl remained doubtful. However, during the Inst twciity-five
thirty years nuiiierous iitterest,iiig esperinic.nts 1i:rre becii pcrf;miiud by Day mid other8 * n[?oti most of thest! Iucliari frcshwater
tishcs, which tend t o prove tliat tlic modilicatioiis i n tlic phnryrgcal region of these creatures (cpibranchial and other organs)
do not contain water for ~r:cii~tcniiig
tlie gills as w;ts origiiially
supposed, but air fur purpost's of direct aerial respir:itioii f . Iu
c.*cri.iiil1other air-breatliiiig fislirs, i. e. the bony G;uioitls aiid the
I)il)iioi, the same end is uttai:ictl by a modification of t h o swiiiiblntlder.
Fiirtlier details upoti this subject arc unnecrssary, as my
(Jl!jCCt is merely to draw atteiitioii to tlie f a c t that aiiioi::. fishes
bcnring no close relationsliip t o c:ich other tlicre nrc t o be found
spvcialized org%:is dif-l'ering iii tlieir niorphologicnl characters,
b u t which a r e all, physiologically speakiiig, lungs.
T l i the East-Indian river* tlicrc is to be fouiid n ciirims nirbrcathing Siluroid, by tiatiic SiS'trccobmnchus,iu which tlic acccmt.iry
respiratory organ takes tlic forin of a p i r of long ~iarro\vairpouches, which lie aloiig t h e back on eithcr side ot'tlic vertebral
column above the tratihversc 11rocesses, and ext,c.ntl f o r three
parts the length of the fish, liotii the brancliial cbaiiiber t o within
four inches of the tail. Ticnous blood is conveyed directly froiii
tlie Iieart t o t h e air-dim by brnnulies of a p i r of the afferent
branchid arterics, and rcturnctl, after oxygenation, iiito tile
n.orta.
has aorltccl oitt i IIC anatomy of'this fisli, describes
I I ~ r t l $ who
,
tlie arrangenient of tlic briiuchid :irteries with rcfimiice t o t l ~ c
&sacs as follows :-" Tlic fourth Icft brancliial artery surpasses
01'
* Day, Proc. Z O U ~SUC.
. lt;tis,11. 274, i i i d Juorn. Liiiii. SOC.(Zoul.) vul. siii.
p. 198; Dobson, Proc. Zool. SOC.lK1, 1). 312.
.t From his researclies on t l i c blim(l-stipply to the w p r a - b r a l d h l cli;rlnbcr
i n thr Ophioceplinlidz, IIyrtl cmsidtzr. t l i o t this organ is nut, I'or breatiiilig
nir, but is probably a water-reservoir f'vi. ~iioisteningt,lie gills. (ITyrtl, '' Uchbep
tlas Labyrinth nnd die Aortenlwgeii t11.r Cinttuiig O1'Aiocc.l,l~it/rts," Sitz. ;lknd.
\Vim. Bd. x. 1853, 11. 1-18,)
~
Silz. . k i t l .
; IIgrtl, '' Zur diiatoiiiie \ C I I I , 5 1 r i ~ . u t J / o >Lo,yi(*,''
.lOl'li>
- Z O l I l . ~ t l ~ \ ~\ t, i
1
\ \ \ .
I
50
bllt. R . 11. U U l t N L OR TUX I O I 1 T I C - h K C I t
all the others on the same side in magnitude. The right, on tlit.
contrary, ia smaller than all preceding it on its Bide. The left
fourth branchial artery leaves the fourth gill-arch to pass to the
ventral wall of the dorsal respiratory sac, ou which i t passes to the
hinder end of the sac, giving off alternating side-twigs. On the
riglit, the artery passing t o the respiratory sac is not tt prolongation of the fourth, but of the first brnncliial artery, and
runs not on the ventral, but on the dorhnl uali of' the sac.''
This statciiicnt of Hyrtl's is endorsed by Hubrecht", who disaeeted m e of these fishes at the requeat of Day \\lien the latter
\I as working at tlic phj siology of this apparatus.
BraiiuLial regioii (nat. size) of' Su'acc.~~h~~nclias~fhssilis,
showing the arrangement,
of tlie braliehid arteries, Been from the vent,rcll aspect.--I, 11, 111, I V , branchin1
arteries ; rs., respiratory sacs.
I n a specimen of Xnccobramhus fossilis in tho Museum of the
Royal College of Surgeons (No. 1061 G), which I dissected last
year, the Erancliial arteries do not answer t o this descriptioii,
f o r herc tlic arteries MC quite q i n n i e t r i d on either sidc. Tl~r:
* 13;1>-,
.J~JUIX, Liun. ~ S b r . (Zuul.) .rvl. riii. 1). 198.
s n m h r or s , i c r o C R iucuus
FO~SILLS.
51
foiirth o n both sides is coiisiclerably larger than the others, and,
a f t e r coursing along the fourth gill-arch, is continued upon t h e
ventral wall of its respwtise air-sac. T!ie first, secoud, and third
AIJ to their several g i h in thc ordinary way.
The h t on the
rif;lit docs not differ in R i m f r o m its companion on t h c left, aiid
r:ipitlly dimiiiishes in calibrc iii i t > course along the gill, so t h a t
I v a s unable to trace it more tlian lialf an inch or YO.
Uiifortunately i t was not possible t o inject this fish ; biit the
vessels were sufficiently couspic~uoust o leave no doubt iii my
mind as t o the accuracy of thiq observation.
It is to b e observed tlint IIyrtl made his observations upon
SnccobrmcLus skqio, so that it is possible that this dislribution
of t h e brsnchial vessels inny h a r e a specific significance, and not
lie merely a case of i o d i \ i d u d Tarintion.
W i t h reference t o this a r r a n p n e n t of t h e aortic arches i n
Saccobranchus, it is interc4ing to briefly review the work t h a t
ling already been donc in conncction n i t h tlio blood-supply t o
organs of aerial rrspiration iii fislicti and the higher Vertubratn.
Beginning a t thc top of t h e s ( d c and working ilownwartls, wc
find that a general law linr heen laid d o ~ mb y Boas” to the eft’ect
that in the Ainphibia ant1 d l Iiighcr Vertcbrata t h e pulmonary
artery is always derived Croin the fourth brmchial aortic arch j-.
This generalization i v consitl(mb1y strengtliened by van Bcmmeln’s $ discovcry iii cnibq onic Reptilia a n d Rves of two gillclefts and an aortic arch 1) iiiqbeti\.een t;hc q s t e m i c aiid pulmonary
arteries ; arid still furtlirr by Zilnmci maiiii’a $ deiiioiistrrttioii of
an aortic arch in the ~ntiicposition in embryos of t h e rabbit
:md Man.
Coming now to the Dipiioi, amphibious fishes nhose swimbladder has been moililiwl for piirposes of aerial respiration,
matters become coniplicatcd I)y thc reduction and compression of
the branchial apparatus. It is posE”ile, hoffevcr, in Ce,*afodz6s,
* Boss, Morph. Jahrh. Bd I11 l S T , 11. 48% “ Urber dcn Coiiiis Arteriosus
und die Arterienbogen der -inipliibien , ’’ :ind Morpli. Jalrrb. lid. X I I I . 1887-83,
1, 115, ‘ <Ueber die Arterit.nbogcndcr \\rirbeltliiere.”
t That is, t l i ~6th Tiwcral i i o r l i c arch. F o r simp1icit)’s rake I count from
t h e 1st brancliial aortic arch.
;Van Eemmcln, “ Die Viwrliltasrlirii n i ~ dnortenbogen hci Rrptilicii ~ ~ n d
V ~ g c l n , ”Zool. hnzeig. lSS(I, l i p X 8 h :143.
4 Ziinniermsnn, “ Urher e ~ i i c t i z Iiuii Aorlrn- imd Piilmriiinthogon gel+
gmpn h‘lcnirnnrtrrin~bo~clr\x%iin I\ iiimrhcn,” A11ntoniiqrlr. hnmip. 18%)
18
j3l.
52
hIII. 11. It. 13UItKE C I S T H E BOILTIC-ARClC
the mcwiber of the fainilp least modified iii this respect, to make
out that tlie smiiii-bladder is sul’plied from t h e fourth aortic
arch”. 111€+ofoptems this is no longcr possible, as t h e efferent
branehial vessclu have brcomo fused on either side into a coiurnon
truiik, fkom the 1) osterior face of’ which the puinionary artery
arises. The bimicliial comprvssion is still inore advauced i u
Lepidosimz 2, tlic reiiiaiiiing iiieriiber of the family : so much so
indeed, t1i:it the p i i l ~ i i o i ~ ~artery
~ r y appareiitly takes its origin
from the third aortic arch. Whether this is really the case I
must leave au opeii question, altliough the great resemblance
between t h e aortic arclies io this fish mid in soiiie of the lowcr
Amphibin $ mould incliiie on? to think not.
I n the two G;uioids Po2yptri.u.s and Anzin 11 the pulmonary
nrtery takes its origiu, accorcliii:,. t o Boas 7 ,as a large branch of
the fourth effereiit braiicliiul v e s s ~ l . Tlie inaiii trunk of this
vessel, after giuiiig off t.hc pu1iiiouai.y artery, passes on in u
reduced condition, xiid joiiis the t h i r d ef’erent branchial vcssel.
Thus Boas reprtls t h e puliiioiiary artery of these fish as it dcrivatire of the fourth branc1ii:tl awtic arch aloiie.
I n coiitradictioii l o this, it a p p a r s , from the figrire of t h e
aortic arches of Amkz given by Rnrnsay Wright, that the third
aortic ~zrchis also iurolved in tlie formation of the pulmonary
artcry. This effect is p d u c c t i by the coiiiiect,ion between the
third aiid fourth efferent braiicliial vessels bei:ig represented
as a branch of the third, and not a contiiiuatiou of the fourth
efferent braucliial vessel. A very slight alterntioii iri the drawing
is enougli to nccoiiiplish this ; for if t.he connection in questiou
is drawn sloping from tlie third braucliiel vessel towards t h e
middle line, it appim-s to be p r t of the third arch; it’ away
froin the middle liiie evcr so slightly, it would be called a continuation of the f o u r t h arch.
* Boas. M q h J d i r b . I3d. Ti. 1880, 11 321, “ Geber IIerz und Srterienbogen bui I’ernfudiia u i i t l I’rot~)pte?.ii.s.”
.(. P a r k e r (IT.N , ) , “ 011the h i s t o m y and Physiology of Pmfopir,rzts (innect e ~ s , ” Tfilil6. Roy. Irish -Acail. vol. ns., iu which paper other references will
also be f o r d .
f IIJrtl, Liy~irZoriimp ~ u d o . a~i d, Bischoff, “ Sur le Lepidusircn pararlurn,”
Ann. Sci. Xat. (Zuol.) vol. xiv. 1840, p. 116.
$ Bischoil. I. C.
11 Juliautiea Niillrr. “ .Beitrip zii B n r i inid G r e i m n d e r Ganoiden,” Abiimill.
Llkad. \Viss. Bcrliii, l N 4 , 1’. I17 ; Um‘, DIorpli. J d i r b , Ed. Ti. p. X I .
U O ; W 3loq~li
,
.7.~111.11.
lkl. v i . I J ~ I:;I?
. S :KII.
hlSTE\I O
r SACCOER LRCItGS FOSStI.lS.
.5 3
IIahing regard t o the fact t h a t Rdinsay Wright’s figure is a
diagram in the Introduction t o a General Natural I-Iistory of
Fivhes ’ *, b u t that Boas, on tho o t l i ~Iimd,
r
was worliing specially
upon t h e aortic arclies of these Ganoida, it seems to me that we
a r e justified in electiug to follow Boas i u this matter, and, with
liiin, to look upon t h e ~ ~ u l n i o n a rartery
y
of Polypferus niid A m i a
a3 a derivative of t h e fourth aortic arch aloue T.
Finally, we come to the mired group of tropical freshwater fisher
in ~ h i c ha modificatioii of the pliaryngeal region does duty as a
lung. Tbe anatomy of tlie epibr:mchial organ of the Labyrinthici
lias been worked out by %,)grafff ; and as regards the bloodsupply t o that structurr, he succeeded, after severd disappointIiimt9, iii proving that thc blood is brouglit to the epibranchial
organ by t h e fourth aortic arch.
The suprabranchia! chamber of t h e Ophiocephalidae, which so
inuch resembles that of the L d ~ y r i n t h i c i ,according t o ITyrtl
does not receive its blood fi*om the henrt, although the f o u r t h
bruuchial artery passes througli it. From t h e subsequrat eqieriiiients tliat have btrii performed on these fi-he3, i t is very
probable t h a t H y r t l n ns ruistd<eii, and t h a t these chambers are
orgalis for t h e respirntioii of air. In this coiinection it is
well t o remember that Zograff’ foiiiid great difficulty in injectinq
t h e blood-vessels t o t lie cpibr:~iichialo i p n i n the Labyriuthici.
Now, as t o Snccobrmtchus, ue have seen that IIyrtl and
Hubreelit found that, the blood ~ v a scarried to the respiratory
sacs by t h e first aortic nrcli o n one side, and the fourth 011 t h e
other. In in: speciiiieii, 011 the contrary, it was supplied by the
fourth on both sldcs.
The peculiar s~)irally-coilctlopihr:iiichial organ of Xeterotis
Ehi-enbe+i, or,e of t h e Osieoglossidae 5, receives its blood from
t h e fourth aortic nrcli, as also does t h a t of Chnnos snlnzonms
(Lutodeira chnnos of Tiyrtl) 11. 111the Cuchia eel, d 4 n ~ h i p n o z ~ s
54
MR. R. 11. DTRXR O U TRE AORTTC-JRCTI
cuckia *, the two respiratory bladders on either side of the neck
obtain their blood-supply froin the first pair of braochial aortic
arches.
I n looking through the above list, one is at once struck by the
frequency with mliich the pulmonary artery is derived from
the fourth aortic arch ; and this not oulg when the lungs are in
all probability homologous structureq, but in creatures having
different kinds of air-breathing organq, some of which can bear
n o morphological relationship to each other.
There certaiuly are exceptions, but they are comparativelp
very few ; in fact, even including Lepidosiren, which, from the
compressed condition of its branchial apparatus, ought scarcely to
be used 8,s an argumeut either \\ ay, they only amount t o three ;
and even of these three we have seen that one, i. e. Succobraizchzcs,
is sometimes found in w h a t may be called the norinal condition.
The general tendency appears to be that any organs modified t o
act as lungs, no matter what may bo their morphological characters, are supplied with blood by the fourth branchial aortic
arch. I n the higher Vertebrata this is the case without exceptiou ;
and even amoiig fishes, where preaumably the organ specialized
for breathing air is not so firmly established, this is still the
case, although liable to variation.
Ximobranchus and AmphQmous agree in respect to the origin
of their afferent pulmonary vessel from the afferent braricliinl
system ; and tlieref’ore it is specially interestiug to note that
X.singio is abnormal in the partial realization of that character
(origin of pulmonary artery from the first branchid arch) which
is diagnostic of Amphipnous.
It lias been suggested to me by my friend a i d late teacher
Prof. Hoaes, that the variations occurring in the pulmonary
artery of these fishes may find a parallel in the variability which
he observed iii the first appearaucev of the epiglottis iu the
Amphibias. So far as I am anare, this may very well be the
case, since there appears to be considerable liability t o variation
iu organs that are In the initial stages of’their development, and,
so t o speak, still on their trial.
* Hyrtl, Ueber den ,tmpliibienkreislanf Ton A i i p h p o i ~ und
s Xompferus,”
Denksclir Shad. Wiss Bd. YIY. 1857. p 39.
I. G. U . Homes, ‘* On EI Iiithei to imrrrogniztd Fcature in thc L irynx of thc
h n r ( i r i - Aiiiphrbi,t ” 1’ 2 5 I W , p 1!11.
ji
SlSTEJI
01.
S.\C('(JIII(ISCLI1'S FOSSILIS.
55
1 cannot coiiclude witliout tendering niy \varnicst tlianks to
Prof. Hen-es for the troiiblc lie 113s talreii in hclpiiig me with tliis
I:aper, and for niany kiiidly suggestions aiid corrections.
NOTE(25 S q t . , 1 S N ) --8iiice writiiig the abovc, my attention
been called to t n o H I : U ~ I p p e r s by Jvbert 011 the aerial
respiration of certain tizlic s of t h e Ainazoii (Ann. Sci. Nat. &r. 6,
\ol. v. art. 8, 6 \ol. \ i i . art. 5). 1 1 1 t h e e inbtauces (Cdlichtlrys,
Ilypostoitios, and Do~(ir\)
:icrinl ri'bpiriition i h effected by iiieans of
n Iictuliar1-y niodifiird poi tioil of t h e iutcsliiie nliich receives its
lilood-supply froiu the "oi 1'1 ; t l i c I~lood,lion crer, iis pait1) venous,
x x the afferent aiid eft( rc~iii 1ji:iricliial i ~ c s s t arc
l ~ contiuuous mid
n l l o ~t b c blood to p:isb t l i w c f l j froin one to tlie other. Iii tlie
lins
c a w of'tRo oihrr i i i h l i r h ( l < , g f h ,i n u b nud S u d ~ s the
) s~iui-bladdrr
f u i i c t i ~ ~ as
i i ~a lung, I
I I I I~ eiious blood fioui thc meseiiteric
\enis, arid also arterial blrwd t i o i n t l i e aorta. It nil1 bc noticed
t l i ; i i all t h e fishes, fir rt g:t~duiheir piilmonary blood-supply,
arc cxcepticins t o the geiicwl triidcncy iudicated above : that this
slioiild be m, espcciially i i i i lie ciihc of the intestiiial breniliera, IS
I I O ~
a nztrtter fot. surpriw ; Iieic., if :nijwherc, ouc aould e i p c c t
t u fiiid \ariatioil, for llie d i h t a n c c : of the inod16ed organ from t h e
~ ) I i : wux
j
suggeats the protiability iliat the blood-supply t o t h e
i w ly~ iicquired l ~ u i giniglit bc lirociired from boiiie a l r c d y exiat iiig iiciglibouring v t shc 1, r:ttIicr ilian directly iiom tlic d i s h i t
aoltlc arch.--R. H.
u.