Dyrets Bevægelser ere temmelig træge; Fødderne og 
Tentaklerne strækkes langt ud og Kroppen ligesom skydes 
fremad, idet Legemet snart forlænges, snart forkortes. Under 
Forkortningen hvælver Ryggen overordentlig meget. 
Rygpapillerne kunne ligeledes forkortes og forlænges, uden 
egentlig at trækkes ind i Legemet; men naar de vare stærk 
sig 
sammentrukne, saa man kun Spidserne af dem, og da skjul- 
tes de stundom ganske, idet at Kraven svulmede stærkt op, 
og dannede ligesom en Kappe, der dækkede Papillerne. 
Kolga ernærer sig væsentlig af Diatomeer og Fora- 
miniferer; den sluger den fine Ler, hvori disse Væsener 
leve, i overordentlig stor Mængde. 
Farven. 
Huden er glasagtig gjennemsigtig, hvidagtig, saa at 
paa Steder. hvor den er sammentrukken, bliver den melke- 
hvid. Tentaklernes 5-lappede Blad, især den af Spikler 
bebræmmede Del, er intens mørk orangegul. Mundskiven 
orangegul med en mørkere, næsten brun Ring om Munden. 
Findested. 
Station 295, Stat. 308. 
Slægtskarakter. 
Legemet bilateralt. Mundskiven, forsynet med 10 
Tentakler, vender mod Bugfladen. Analaabningen paa Ryg- 
siden. Paa den forreste Del af Ryggen en fremragende 
Krave, forsynet med Papiller. Strax foran denne to Aab- 
ninger, | for Kjønsorganet og 1 for Stenkanalen. Fodder 
paa begge Sider af Kroppen og omkring dennes bagerste 
Ende, Kjønnet adskilt. Ingen Tarmappendices (Lunger). 
Artskarakter. 
Legemet 50”” langt, 15—20”" hoit og 12—15”” bredt. 
Ryggen stærk hvælvet; paa Kraven 6 paa tvers staaende 
Papiller, hvoraf de to midterste ere de længste. 16 lange, 
tykke, næsten retraktile Fødder, hvoraf 5 paa hver Side og 
6 omkring den bagerste Ende. Kroppens Hud gjennem- 
sigtig. Tentaklerne 5-lappede, hver Lap 3-fliget. 
Førend vi anstille nogle almindelige Betragtninger over 
det nu beskrevne Dyr, skulle vi omtale med nogle Ord Dr. 
H. Théel's smukke og i flere Henseender interessante Ar- 
beide over Slegten Elpidia. Vi gjøre dette saa meget 
desto hellere, som vi have havt en god Del Exemplarer af 
dette Dyr til vor Raadighed, hvorved vi Skridt for Skridt 
ikke alene have kunnet følge hans Observationer; men ogsaa 
i det Væsentlige have kunnet constatere deres Rigtighed. 
Da Dr. Théel ikke har kunnet disponere over ret mange 
Den norske Nordhavsexpedition. Danielssen og Koren: Holothurider. 
17 
This seems rather a sluggish species; its movements 
are effected by stretching out the suckers and tentacula and 
alternately elongating and contracting the trunk, the body 
being as it were jerked forward. During each contraction 
of the trunk the back is remarkably arched. The dorsal 
papille also admit of being shortened and lengthened, with- 
out however being strictly retractile; but when contracted 
to their full extent, the points only were visible, nay some- 
times no part of the papille could be discerned, the collar 
swelling out and covering them as with a mantle. 
Kolga subsists chiefly on. Diatomacee and Foraminifera, 
by swallowing the soft clay im. which these animals are 
embedded : in enormous quantities. 
Colour. 
The skin is glassy, translucent, whitish, — milky-white 
when contracted. The tentacular, five-lobed pinne, more 
especially the part bordered with spicule, are of a deep, 
vivid orange. The oral disk orange, with a darker, almost 
brown ring round the mouth. 
Locality. 
Stations 295, 303. 
Generic Character. 
Body bilateral. The oral disk, furnished with 10 
tentacula, facing the ventral surface. The anal aperture 
on the dorsal surface. On the anterior portion of the back 
a papillous, projecting collar. Immediately anterior to the 
collar two circular openings, .the respective outlets for the 
genital organ and the sand-canal. Suckers on both sides 
of the trunk and round the terminal extremity. The sexes 
separate. No intestinal appendages (respiratory tubes). 
Specific Character. 
Body averaging 50”” in length, 15”"—20”” in height, 
and 12”"—_15””" in breadth. The back exceedingly arcuate ; 
the collar furnished with 6 transverse papille, the middle 
pair the longest. Long, thick, almost retractile suckers, 
16 in number, 5 on either side, and,6 round the terminal 
extremity. Skin of the body translucent. The 
five-lobed; each lobe subdivided into three lobules. 
Before proceeding to supplement our description of 
this animal with a few general remarks, we will briefly 
notice Dr. H. Théel’s elegant and valuable treatise on the 
genus Hlpidia. We feel indeed specially called upon to do 
so, having had the good fortune to obtain a very consider- 
able number of specimens of the animal in question, enab- 
tentacles 
ling us successively to renew his observations, which in all 
essential particulars coincide with our own. Unfortunately, 
the number of individuals examined by Dr. Théel was but 
2 
ro) 
