Exemplarer, 
mindre udtommende, end Tilfældet havde været under gun- 
stigere Omstendigheder. Vore Observationer kunne for- 
haabentlig 1 nogen Grad raade Bod herpaa. 
I det indre Bindevævslag hos Elpidia have vi fundet 
lignende elliptiske, skivedannede Kalklegemer, som de vi 
have beskrevet og afbildet hos pa. Hvad Muskulaturen 
betræffer, saa ere de saakaldte Ringmuskler paa den forreste 
og bagerste Del af Kroppen virkelig cirkulere, som af 
Théel bemærket, men paa den midterste Del gaa de ikke 
rundt, men ophøre enten ved Randen af Længdemusklerne 
eller et ganske lidet Stykke mdenfor Randen, henimod 
Midten. 
Vandkarsystemet hos Elpidia er ifølge vore lagttagelser 
temmelig overensstemmende med det hos Kolga og Irpa. 
Fra Vandkarringen udgaa 5 temmelig korte Hovedstammer, 
hvoraf de to, der tilhører Biviet, dele sig hver 1 2 Grene, 
der gaa til hver sim Tentakel, de to Sidestammer dele sig 
hver i 3 Grene, af hvilke den ene, som er den største, 
danner Længdekanalen, medens de to andre gaa til hver 
sin Tentakel; de 5 Hovedstammer dele sig altsaa i 12 
Grene. | 
Dr. Théel har kun iagttaget 2 Sidekanaler, der efter 
ham udgik fra Vandkarringen; men han gjør udtrykkelig 
opmærksom paa, at han paa Grund af Undersøgelsérnes 
Vanskelighed ikke har havt tilstrækkeligt Materiale for at 
komme til fuld Sikkerhed. Hvad der især tiltrak sig vor 
Opmærksomhed med Hensyn til Vandkarsystemet hos El- 
pidia, 
Længdekarrene (se Mémoire sur PElpidia par H. J. Théel, 
Tab. 5, Fig. 28, 29, C, 0), og det saameget mere, som 
han ikke har fundet nogen Kontinuitet i Cirkulationen, idet 
de antaghe Skillevægge ikke vare forsynede med nogen Aab- 
ning, men vare i hele Circumferentsen fastvoxede til Kar- 
rets indre Væg, saa at der skulde være et særeget afsluttet 
Rum imellem 2 Skillevægge, og fra dette Rum skulde 
Karret udbugte sig og danne Fodampullen. 
Den oveneiterede Afbildning, som ledsager Beskrivel- 
sen, er i det Væsentligste aldeles korrekt; men da Dr. 
Théel ikke har iagttaget nogen Kontinuitet i Længdekarrets 
Lumen, — er hans Opfatning bleven ganske forskjellig fra 
den, «vore Undersøgelser have ledet os til. Nogen fuld- 
stændig Injektion af Længdekarret er det ikke lykkedes os 
at foretage; derimod have vi kunnet drive de i Injektions- 
vædsken indeholdte Luftblærer igjennem Karrets hele 
Længde, hvorved vi have overbevist os om, at Længde- 
kanalen ikke er afbrudt ved Skillevægge; men at Vand- 
vædsken uhindret cirkulerer hos Elpidia ligesom hos andre 
Holothurider ". 
* Herover have vi nærmere udtalt os i en Afhandling optaget i 
“Magazin for Naturvidenskaberne,” 25 Bind, pag. 101. 
ere Undersøgelserne 1 enkelte Dele blevne 
var de af Théel beskrevne Skillevægge (Klapper) i. 
18 
limited, and hence his results are less comprehensive. than 
would otherwise have been the case. Our observations will, 
we hope, serve to complete his description. 
In Elpidia we have detected in the inner layer of 
connective tissue elliptic, discoid calcareous corpuscles sim- 
ilar to those occurring in Jrpa, which are described and 
figured in our paper on that genus. With regard to the 
muscular development, the so-called annular muscles on the 
anterior and posterior portions of the trunk did indeed 
prove to be strictly circular, as noticed by Dr. Théel, but 
in the medial region their form is not that of a perfect ring, 
since they terminate at the margin of the longitudinal mus- 
cles or almost immediately within it, never meeting in the 
middle. 
The aquiferous system in EHlpidia, according to our 
observations, presents a close resemblance to that in Kolga 
and Jrpa. From the vascular ring protend 5 principal stems, 
comparatively short; 2 of these, belonging to the bivium 
divide dichotomously, each of the branches proceeding to a 
tentacle; the two lateral stems divide trichotomously, one 
of the branches — the largest — forming the longitudinal 
canal; the remaining two ‘proceed each to a tentacle. he 
5 principal stems divide therefore into 12 branches. 
more than 2 lateral 
issue from the 
Dr.. Théel has not observed 
canals, which, according to his diagnosis, 
water-vascular rig; but he lays particular emphasis on the 
fact, that with so complex a structure the materials be- 
fore him were insufficient to arrive at absolute certainty. 
A characteristic peculiarity connected with the aquiferous 
system in Elpidia that attracted our special notice, was the 
valvular septa in the longitudinal vessels, minutely described 
by Dr. Théel (vide Mémoire sur /’ Elpidia, par H. J. Théel, 
Pl. 5, figs. 28, 29, C, C), particularly since that naturalist 
has failed to detect any continuity in the circulation, the 
supposed septa not being furnished with an aperture, but 
having their whole circumference connate with the inner 
wall of the vessel; hence two septa would enclose a sepa- 
rate space; and from this space the vessel is said. to bulge 
out, forming the pedal ampulla. 
The figure accompanying the description referred to 
above, agrees in the main with what we have ourselves ob- 
served, but Dr. Théel not having detected any continuity 
in the lumen of the longitudinal vessel, he naturally enter- 
tains on this point quite a different view to that which we 
have been led to adopt. A complete injection through the long- 
itudinal canal we have failed to effect, whereas the bubbles 
of air contained in the fluid mjected were repeatedly forced 
down the entire length of the vessel, affording to us satis- 
factory proof that the longitudinal canal is not interrupted 
in its course by septa, but that the aquiferous fluid cireu- 
lates freely in Elpidia, as in other Holothurians.! 
1 We have treated this subject more at large in a Memoir 
which appeared in “Magazin for Naturvidenskaberne,” 25 Bind, pag. 101. 
