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Notes on a Sapphirina and a Salpa caught off the Cape of Good Hope

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240

NOTES

ON

ASAPPHIEINAANDA

SALPA

CAUGHT

OFF

THE

CAPE OF

GOOD

HOPE.

By

John McCance,

F.R.A.S.

[Rexd August llih, 1884.]

In offering the following notes to the Royal Society of Tasmania, I

must

apologise forthe paucity of original obser-vationwhich will be apparent, and plead as

my

excuse

my

hope that they

may

arouse a little interest in the less con-spicuous forms of oceanic life, of which I believe the seas round Tasmania contain a

number

of interesting species.

When

I captured these animals I was a passenger on board the ship Invercargill, Captain

John

Muir, then on a vovage from

London

to Port Chalmers, N.Z.

At

noon on January 26, 1883, the ship's position was40° 38' S., and 17°

30' E., and from the following day'srun and position,I

calcu-late

we

were in 40° 40' S., and17° 35' E., at the time

when

I

obtainedthese specimens.

The

day was dull, but not cold,

andthe temperature of the sea, as taken by the mate, was higher than on preceding days. Unfortunately, I did not

make

a noteof the exact temperature,butI imagine

we

were passingthrough one of those patches of

warmer

waterwhich have been remarked to the southwardof the Cape of

Good

Hope. Nothing unusual was noticed in the appearance of thesea,which was calm, until the afternoon,

when

thewater

wasfilledwith brilliant blue stars, floating past the ship in

greatnumbers.

With

a small canvas bag I succeeded in

fishino-

up

several of the blue stars, which were a speciesof Sapphirina, and two or three other animals, non-luminous, oneofwhich wasa Salpa democratica. 1kept

them

inaglass ofsea watertillthe 29th,

when

an unfortunate accidentkilled them,andhaving only a small magnifyingglass, Iwas pre-ventedfrom making a full examination of all. I preserved

the sketches Iwas able to make, and throughthe kindness of

Mr.

Morton, of the Eoyal Society's

Museum,

I lately

re-ceivedfrom Mr. Haswell, of Sydney, information as to the species andconstruction of the animals depicted.

The

two small crustaceans correspond so closely with the descriptions and drawings of the male and femaleof Sapphi-rina gemma,asgiven

by

J. D.

Dana

("Crustacea," Part II.,

pp. 1252-3; Atlas, Plate88,figs. 1and2),thatI

am

very con-fident thatthey are individuals of thatspecies. Dana's

speci-mens

werecaughtonthe Agulhas Bank, Southof theCape of

Good

Hope, in 1842, April 11 and 12, andhe notes that a Sapphirinaofprobably the same specieswas caught 12 miles N.E. of

New

Zealand.

He

speciallynotes the brilliantblue reflections of the male, the water on the Agulhas

Bank

being spangled with

them

for several hours.

(4)

241

aninch broad, and its body is composed of ten segments, the last being almost absorbed in the ninth, which again

is

much

smallerthan the eighth. Its activitywas remarkable, anditsmotion sinuous, like that of the Sole.

The

female is

aboutiofan inchlong, and £%of aninchbroad; its

cephalo-thorax hasfive joints, and its

abdomen

six.

On

either side of the abdomen, and springing from the junction of

abdomen

andthoraxisabagof very

numerous

small eggs, about

J

¥ of aninchlong,and

^

of an inch broad, of an elongated egg-shape.

The

female,like the male, was extremely nimbleand

active, and

swam

swiftly round and round the glass.

The

eggsacs,while the animalwas in motion,were

made

to rapidly approach and recede from one another, thus appearing

more

likeorgans of locomotion. Both sexes appeared to

me

tohave a finely granulated exterior, and a uniform dull lavender colour. Inthehead of each were apair of elongated bronze red specks,the eyes accordingto Dana.

The

otheranimal which Iexamined was one of those very curious Tunicates, the Salpae democraticae. This Salpa,

Mr.

Haswell writes me, "develops no sexual glands, but give origin

by

buddingto a chainof

young

"

Salpaemucronatae

each differing considerably from Salpa democratica. These remain,throughlife, united ina chain, and"each

when

adult develops a single egg from which a Salpa democratica is

developed."

The

solitary Salpawhich I hadthe good fortune tocapture, contained,

when

caught, a chain of

young

which were distinctly visible through the transparent body of the Salpa, curled round at the posterior end of the internal

cavity.

Next

morning,

when

daylight permitted a more

de-tailedexamination. Ifoundthe chain of 80-90 minuteS. micro-nataejustescapingfromthe S. democratica, thelastpairofthe chain becomingdetached afew

moments

afterI got

them

under observation. This chain consisted of a double row ofanimals, sosmallthatwith

my

inferiormagnifierIcould onlysee

them

as egg-shaped transparent masses, about ¥x

¥ofaninchlong, with apurpleknobat one end anda purple streak in the interior.

The chainwasaboutIfofan inch long, and floatedwith the purple knobs uppermost, in a curved shape, whichvariedas theindividuals performed their occasional simultaneous

con-tractions.

The Salpa democratica wasabout |an inchlong, orfof an

inch, ifthe taperingconicalprocesses at the posteriorendare included. Itsbreadth was about \ of an inch, andits shape thatof abarrel, orsquare-endedegg.

The

tunicwas perfectly transparent, and the whole animal colourless, except the main parts of the nervous system,which were of abeautiful purple, and a few spotsof a similar purple,which were, I

(5)

242

integumentof the body, as viewed from above,below, orone

side, appeared distinctly to be

composed

of several layers, caused, as Mr. Haswell informs me, by the outer covering beingof quite different substance and consistency from the

rest.

A

series of six narrow ribbons, finely striated longi-tudinally,andlying apparentlyin one of the inner layers of theintegument, formedan efficient muscularsystem.

About

oncein five seconds, as far as I recollect, theywere slowly contracted and

more

rapidly expanded, the resulting expul-sionof thewater in the interiorcavityproducing a forward

jump

of about an inch.

The

sixth band, or ribbon

that nearestthe processes atthe posteriorend

did not completely encircle the body,but was interrupted for a space of about one-sixth of its length, on the dorsal side of the animal

by

that I

mean

the side which was generally uppermostas the Salpafloated, and isopposite to thatfrom which theposterior processesspring.

The

fifth and fourthbands touched on the dorsal side ; thefourth,third, and secondsimilarlylay in close

juxtapositiononthe ventralside.

The

waterwhich is ejectedby these muscular bands is ad-mittedbya wide orifice,with projecting thick lips, situated inthemiddle of the anteriorendof theSalpa, andthese lips

werecontinuallyandregularly 'openingandshutting. Iwasable to

make

a sketch of theorifice,butdidnotarrive atan examina-tion ofthe posterior one, which lay somewhere aboutthelong processes. Just behind the anterior orifice, and

making

an

angle of about 45° with the plane dividing the dorsal and ventral halves of the animal, wasa roughly triangularpurple vein or thread, havingin the centre ofthe space enclosed a purple dot, with a few fine radiating purple lines. These, accordingtoMr. Haswell's letter, are the nerve ganglionand eye spot.

From

the centre of the base of the triangular nerve, and runningalong the dorsal side oftheinternal cavity of the Salpais the endostyle,which is purplein colour,and abouty3n ofaninch inlength, orfofthelength of the Salpa's body.

From

the apex of the triangular nerve is a similar purple vessel, runningin anirregularcurveback to the pos-teriorendofthe animal. This is the main blood-vessel, and closeto itsfurther endlies the heart.

The

heart struck

me

as very remarkable, and1 spent

some

time in watching it,

andnoticed thatthe

membranes

initflapped for a period, then paused, then flapped differently, then paused, then flapped as before. I did not then

know

that these Tunicates have a heartwhichfirstdrivestheblood forwardfor a certain

number

(6)

The

twoposterior processes to which I have referred were apparentlyofthe same substance as the outer tunic.

They

werebroadly conical at the base,which wasaboutfof their

totallength; the outer \ werevery

much

finerandnarrower,

andcovered withminute dots, which, Mr. Haswellsays,were probablyminute spines. In the interior of the baseof each was a very strange mushroom-shaped object, of which Mr. Haswell sayshe does not

know

its precise nature, though he

knows

it to be as I describedin

my

letterto him.

When

I

sketched the process, or horn, I noted themushroom-shaped object as coloured metallic green,butifIrecollect rightitwas

of the same brightpurpleas thenerveganglion,etc.,

when

the animalwas first caught.

Ihave not been able to find anydetailed account of the Salpae in the Society's Library, but in the Proceedings of the .Boston Society of Natural History, Vol. XI.,p. 17, is a detailed description, with woodcuts, of SaVpa Cabotti,

by

Alexr. Agassiz. This is found southof Cape Cod,and very closely resembles the one I caught, and the description and investigation into the connectionofthe chain forms arehighly interesting.

CANCER

IN

CATTLE.

[Paperread before thePoyalSocietyofTasmania August11th 1884,

By

H. A.PerkinsM.D., Edin.]

The subjectof disease in cattleisonewhich cannotfailto interest

allsections of thecommunity, aswell thestockowner who provides

forthemarketasthe inhabitantsoftownswho consume the meat, andtowhose advantageit must be to obtain the most wholesome supplyoffood. Ata timewhencanceramong

human

beings has *been said tobe ontheincrease, the natureof such disease among

cattlenotonly merits attentionatthehandsofveterinary surgeons, but furnishes materialforspeculationtomedicalmen. Forinthese daysofminuteorganiclife, ofmicrococciandbacilli, ata timewhen

so

many

diseases findadvocatesfortheiroriginand development in

thetheory ofcontagiouslivingorganisms, itmight bea fair

deduc-tion todraw that the disease in

man

derived its prevalence and potencyfromlivingspores transmittedfromthe diseasedmeat which we colonists so unsparingly consume. The more especially as

specimensofsuchdisease calledcancerin cattleareneither few nor hardtofind,andthe descriptionofOsteoSarcoma whichI

am

about

to give,isbased on examplesobtainedinTasmania. "Thetime has

[*Statisticsof last14 yearsshowthatthoughthere hasbeen anincreaseinthenumber

of deathsfromthiscause,yet that the population has increased in nearly the ~~

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