51 
taet bprstebesatte Led. Det midtersto Halevedlueng njesten 
qvadratisk, kun lidet lsengere end bredt, med Sidekanterne 
i den bagre Halvpart forsynede med s'maa Tomer; det 
bagre Indsnit bredt. vinklet, med Kanterne tint saugtakkede, 
Endelapperne tilspidsede og beveebnede med en enkelt apical 
Torn. De ydre Halevedhsengs indre Plade kortere end den 
ydre og langs den indre Kant under Randbprsterne tset 
tandet. Hele Legemet gjennemsigtigt, af lividagtig Farve, 
uden Spor af Pigmentering. 
Findesteder. Stat. 295, 297. 
Bemasrkninger. Pen i min Prodromus givne Dia- 
gnose er kun affattet efter det under vor Expedition tagne 
enkelte Exemplar, paa bvilket forskjellige i system? tisk 
Henseende vigtige Dele manglede eller var ufuldsteendige. 
Lfenge efter Expeditionens Afslutning og efterat nservserende 
Afhandling allerede var paabegvndt. blev imidlertid af R. 
Collett i Ventrikelen af den mairkelige nye Dvbvandsfisk, 
Rhodichlhys regina, Coll., fundet Levningerne af et andet 
Exemplar af samme Art, paa hvilket saavel Antennebladene 
som samtlige Fodder var i Behold. Jeg har lierved i en- 
kelte vigtige Punkter kunnet supplere min tidligere Ohar- 
acteristik af nservajrende interessante Myside og liar paa 
sidste Planclie vedfoiet de fornodne Figurer. 
Beskrivelse. Da begge de foreliggende Exemplarer, 
som ovenfor bemmrket, er i en stserlit mutileret Tilstand, 
Oliver det temmelig vanskeligt med Sikkerbed at bestemme 
Cegemets almindelige Form. Den synes imidlertid, efter 
de erlioldte Levninger at demine, at have vseret forholdsvis 
undersmtsig og nmrmest lignende samme hos Arterne af 
klsegten Mysideis, G. 0. Sars. 
Rygskjoldet er forholdsvis stort og synes fuldstaendigt 
at have daekket Forkroppen. Det er fortil (se PI. "V , Fig. 
] 3, og PL XX, Fig. 18) betydelig bredere end Bagkroppen 
°g viser foran Midten en tydeligt markeret buet Cervical- 
fure. Pandedelen springer staerkt frem og er i Midten ud- 
trukken i en skarp tilspidset, rostrumlignende Fortsats, der 
rsekker na-sten til Midten af lste Par Foleres Basalled. 
0iuene (ibid.) er ganske og aldeles rudimentaere, kun 
dannende et Par skraat udadrettede, stumpt koniske Fort- 
satser, uden det mindste Spor af Pigmet eller Synselementer. 
Ved den stumpt tilxundede Ende, der ikke nekker ud 
over Rygskjoldets Sidekanter, lindes fortil et lidet tand- 
formigt Fremspring. 
lste Par Foleres Skaft (ibid.) er temmelig kraftigt 
bygget, cylindriskt og omtrent af samme Lsengde som Ryg- 
skjoldets Brede fortil. Af dets 3 Led er lste og sidste 
omtrent lige store, medens det 2det er ganske kort. 
Svoberne var vistnok paa begge Exemplarer incom- 
plette; men efter det bevarede basale Parti lader sig do a 
slutte, at de har vmret af temmelig betydelig Lscngde. . 
2det Par Foleres Blad var paa det ene stprre Ex- 
emplar (PI. y. Fig. 13) paa begge Sider defect, idet den 
ydre Del var afbrukket. Derimod var det paa det andet 
nhndre Individ (PI. XX. Fig. 18) uskadt og forsynet med 
and divided into 7 or 8 short articulations, densely beset 
with bristles. Telson well-nigh quadrate, but vei \ little 
longer than broad, armed in the posterior half with small 
marginal denticles; posterior incision broad, angular, with 
the edges finely serrate; the terminal lobes pointed and 
armed with a single apical spine. Inner plate ol outer 
caudal appendages shorter than outer, and, along the inner 
margin, closely dentate beneath the bristles. Whole body 
translucent, and whitish, without any trace of pigment. 
Locality. — Stats. 295, 297. 
Remarks. — The diagnosis given in my Prodromus 
was worked up exclusively from the solitary specimen taken 
on the Expedition, in which however several systematically 
important parts were either entirely wanting or incomplete. 
Long after the close of the Expedition, and after the pi esent 
Memoir had been commenced, Mr. R. Collett found in the 
ventricle of the remarkable deep-sea fish, Rhodichthys regina, 
Coll., the remains of another specimen of the same species, 
in which both the antennal scales and all the feet remained 
intact. Hence, I have, with regard to several important 
points, been enabled to supplement my original characteristic 
of this interesting form, and on the last plate have annexed 
the necessary figures. 
Description. — Both of the specimens secured being, 
as mentioned above, in a very mutilated condition, it is a 
matter of some difficulty to determine the general form of 
the body. This, however, judging from the remains found 
on the Expedition and by Mr. Collett, would appear to be 
comparatively thickset, approximating closest that in the 
two species of the genus Mysideis, G. 0. Sars. 
The carapax is comparatively large, and would appear 
to entirely cover the ceplmlo-thorax. Anteriorly (see PI. V, 
fig. 13, and PI. XX, fig- 18), it is much broader than the 
posterior division, and exhibits, anterior to the middle, a 
well-defined, arcuate cervical groove. The frontal part juts 
prominently forward, and is drawn out as a sharp-pointed, 
rostrum-like projection, reaching almost to the middle of 
the basal joint of the 1st pair of antennae. 
The eves (ibid.) are in every sense rudimentary, form- 
ing merely a pair of obtuse, conical prolations, directed 
obliquely outward, without the slightest trace of pigment 
or visual elements. At the obtusely rounded extremity, which 
does not reach above the lateral margins of the carapax, 
occurs anteriorly a small dentiform projection. 
The peduncle of the 1st pair of antennae (ibid.) com- 
paratively powerful in structure, cylindric. and about as long 
as the carapax is broad anteriorly. Of its 3 joints, the 
first and last are about equal in size, while the second is 
exceedingly short. 
The flagella were in both specimens incomplete; but, 
judging from the basal portion, their length may be inferred 
to have been considerable. 
The scale of the 2nd pair of antennae was in the 
larger example (PL V. fig- 13) on either side defective, the 
outer portion having been broken off. In the smaller spec- 
imen (PI- XX, fig. 18), it was wholly uninjured and 
