og er ikke funden nordligere, end ved Bergen. Det er nu 
til dette Dyr, Hamingia arctica slutter sig mest, idet den 
danner en interessant Oyergangsform; kun maa vi beklage, 
at vi kun have havt 1 Exemplar til vore Undersøgelser. 
Ydre Karakterer. 
Legemet er cylindrisk med en glat, lidt slimet Over- 
flade, er 120” langt, 20”” tykt paa Midten, men smalner 
noget af mod begge Ender, Fig. 1. 
Den forreste Ende er langstrakt, but afskaaren, og 
paa den findes Mundaabningen, der danner en Spalte med 
tykke, foldede Lieber, og vender mod Bugfladen, Fig. 1, a, 
2, a. Omkring Mundaabningen sees to halvmaaneformige 
Hudfolder, Fig. 1, 0, 2, b, der paa Rygfladen ere temmelig 
fremspringende og staa et Stykke fra hinanden, imedens de 
mere og mere nærme sig hinanden mod Bugfladen, hvor 
den forreste Fold forener sig med den bagerste 1 en stump 
Vinkel, Fig. 2, c, saa at der bliver en liden Del af Mun- 
den, der ikke omfattes af de nævnte Folder. Imellem den 
forreste Fold og Munden er en yderst smal Indsynkning, 
hvorved Mundlæberne blive ligesom mere fremtrædende, 
Fig. 2, d; men imellem den forreste og bagerste Fold er 
Indsynkningen baade bredere og dybere, Fig. 2, e. Disse 
Folder kunne vel betragtes som en rudimentær Snabel. 
Omtrent 20” fra Mundpartiet findes paa Bugsiden 
to lange, cylindriske, krumbøiede Papiller, der staa ved 
Siden af hinanden, og paa hvis fri Spids, der vender mod 
Munddelen, iagttages en fin Aabning, Fig. 1, c, 2, f. 
Kroppens bagerste Ende er afrundet, og i dens Cen- 
9 
trum sees den runde Analaabning, Fig. 3. 
Huden. 
Huden er blød, halv gjennemsigtig, og dannes af en 
yderst tynd, strukturløs Cuticula, Fig. 4, a, der dækker 
det hyaline Bindevævslag, som er temmelig bredt, og hvori 
er leiret dels enkeltvis, dels i Grupper, Celler, Fig. 4, 0, 
5, a, imellem hvilke sees uformede Pigmenthobe. Her 
findes ikke noget Fpithellag; men de nævnte Celler, der 
som oftest ere fyldte med et finkornet, grønt Pigment, saa 
at Kjernen ganske skjules, kunne i større Strækninger 
være enkeltvis sammenhængende, og faar da et epithellig- 
nende Udseende, Fig. 4, c, imedens tilgrændsende Steder 
kunne være ganske blottede for Celler. Imellem disse Pig- 
mentceller, men som oftest dybere end dem, sees aflange 
Bindevævslegemer. 
Indenfor det hyaline Bindevævslag er Muskelhuden, 
der bestaar af 3 distinkte Lag, nemlig Ringmuskler, Længde- 
muskler og Skraamuskler. 
Ringmusklerne ere de yderste og ligge nærmest det 
hyalme Bindevævslag; de bestaa af smale Fibriller, der 
coast, and has nøt been taken farther north than Bergen. 
Now it is this animal with which Hamingia arctica exhibits 
the closest agreement, representing a transition-form of very 
considerable interest: we regret however to state, that we 
have had but one specimen whereupon to base our obser- 
vations. 
External Characters. 
Body cylindrical, with a smooth and slightly mucid 
surface, 1207” long, 20”” thick in the middle, but nar- 
rowing a little towards the extremities, fig. 1. 
On the anterior extremity, which is elongate and ob- 
tusely truncate, occurs the buccal opening, as a slit or 
cleft, with thick, folded lips, facing the ventral surface, 
figs. 1, a; 2, a. Round the buccal opening extend two 
lunate cutaneous folds, figs. 1, 6; 2, b, rather prominent 
on the dorsal surface, and a little apart, whereas they 
gradually converge on the ventral surface, and form an ob- 
tuse angle, fig. 2, c, leaving a small portion of the mouth 
which the said folds do not encircle. Between the anterior 
fold and the mouth, occurs an exceedingly narrow depres- 
sion, which gives increased prominence to the buccal labia, 
fig. 2, d; between the anterior and posterior folds, the de- 
pression is broader and deeper, fig. 2, e. These folds may 
be regarded as a rudimentary proboscis. 
About 20”” from the buccal region, on the ventral 
surface, are seen two long, cylindrical, arcuate papillæ, 
placed side by side, the free extremity of which, facing 
the buccal section, is furnished with a minute aperture, 
meas, 1 OS Å, jo 
Posterior extremity of the body rounded, with the 
anal orifice m the centre, fig. 3. 
Skin. 
The skin is soft, semi-translucent, and consists of an 
exceedingly thin, structureless cuticle, fig. 4, a, covering 
the hyaline layer of connective tissue, which is compara- 
tively broad, and has dispersed throughout it, either isolated 
or in groups, a number of cells, figs. 4, b; 5, a, between 
which are seen amorphous lumps of pigment. There is 
no epithelial layer; but the cells are generally full of a 
finely granulous, green pigment, by which the nucleus is 
entirely hidden, and being sometimes connected, two and 
two together, they resemble epithelium in appearance, fig. 
4, c, whereas spots directly adjacent will be sometimes al- 
together destitute of cells. Between these pigmentary cells, 
but, as a rule, deeper down, are seen elliptical corpus- 
cles of connective tissue. 
Underneath the hyaline layer of connective tissue, 
extends the muscular integument, composed of 3 distinct 
layers, viz. a layer of annular muscles, a layer of longitu- 
dinal muscles, and a layer of oblique muscles. 
The annular layer, adjoming the hyaline layer of con- 
muscles consist of 
nective tissue, is the outermost; its 
