sale Lob betydelig storre end den ventrale. Forste 
Par Svommefodder med Yderkanten af den ydre 
Gren kun forsynet med 3 Smaatender, umiddelbart 
ovenfor den Iste Endetorn. Halegrenene noget kor- 
tere end de 2 bagerste Segmenter tilsammen, Far- 
ven hvidagtig, uden Pigmentering. ' Dyrets Leengde 
9 mm. 
Bemerkninger. Den her omhandlede Art staar 
vistnok meget ner foregaaende, men er dog let 
kjendelig fra samme ved forskjellige vel udpregede 
Characterer, hvoraf navnlig maa fremheves den 
rudimentre Beskaffenhed af Oinene og Pandepladens 
Form og Bevebning. Ogsaa i Bygningen af de for- 
skjellige Kropsvedheeng vil man ved en ngiere Sam- 
menligning kunne paavise en Del mindre Differentser 
fra samme hos W. bipes. 
Beskrivelse. Legemets Form hos Hunnen (se 
Pl. 1, Fig. 4) stemmer idethele temmelig noie over- 
ens med samme hos foregaaende Art, skjondt den 
maaske er noget mindre slank. Hannen er endnu 
ubekjendt. Rygskjoldet er som hos .V. bipes steerkt 
sammentrykt og viser, seet fra Siden, en temmelig 
regelmessig oval Form, med den storste Hoide, der 
er noget storre end den halve Lengde, omtent paa 
Midten. De frie Kanter af Valvlerne er nedentil 
jevnt buede og danner helt fortil en sterk Krum- . 
ning, inden de steder sammen ved Basis af Pande- 
pladen. Bagtil viser de sig skraat afskaarne i Ret- 
ningen forfra bagtil, og de nedre bagre Hjorner af 
Rygskjoldet danner derfor, som hos foregaaende Art, 
til hver Side en smalt afrundet Lap, der dekker 
Siderne af Bagkroppen og nesten rekker til Begyn- 
delsen af Halen. Pandepladen (se Pl. IV, Fig. 9, 10) 
er vel udviklet og af meget smal tungedannet Form, 
temmelig sterkt hvelvet oventil, og forsynet i En- 
den med et spidst tornformigt Fremspring, der dan- 
ner Fortseettelsen af en langs den nedre Side lebende 
Kjel- Sidste Bagkropssegment har, som hos fore- 
gaaende Art, et Par smaa afrundede Epimerer og 
er ligesom de 3 folgende Halesegmenter grovt sag- 
_takket i den bagre Kant. Halegrenene er noget 
kortere end de 2 foregaaende Segmenter tilsammen, 
forovrigt af fuldkommen samme Bygning som hos 
toregaaende Art. 
Minene (se Pl. IV, Fig. 9, 11) udmerker sig i 
hoi Grad ved sin ringe Stoerrelse og rudimentere 
Beskaffenhed, og rager kun lidet frem fra Rygskjol- 
det, hvorfor de let kan forbisees. De er, som hos 
N. bipes, deekkede oventil af en skjelformig, spidst 
udlobende Plade. Selye Qienstilken er af konisk 
R2 
recurved at the tip and furnished with long di- 
vergent plumose bristles; the epipodite with the 
dorsal lobe considerably larger than the ventral 
one. First pair of swimming feet with the ex- 
terior edge of the outer branch furnished only with 
3 small teeth immediately above the 1st terminal 
spine. Caudal rami somewhat shorter than the 2 
backmost segments taken together. Colour whitish, 
without pigmentation. Length of the animal 9 mm. 
Remarks. The species here spoken of is cer- 
tainly very nearly allied to the preceding one, but 
still is easily distinguishable from same by various 
well defined characteristics, of which may especially 
be noticed the rudimentary character of the eyes, and 
the shape and armature of the frontal plate. Also 
in the structure of the various appendages of the 
body, we may, on a closer comparison, be able to 
notice a number of smaller differences in the same 
from those of N. bipes. 
Description. The shape of the body of the 
female (see Pl. I, fig. 4) agrees, on the whole, pretty 
exactly with, that of the preceding species, although 
it is, perhaps, somewhat less slender. The male is 
yet unknown. The earapace is, as in WN. bipes, 
strongly compressed and exhibits, viewed laterally, ” 
a pretty regular, oval form; with the greatest height, 
which is ‘somewhat more than half the length, at 
- about the middle. The free edges of the valves are 
evenly curved below, and form, quite in front, a 
strong curvature until they unite at the base of 
the frontal plate. At the back they show them- 
selves obliquely truncated in a direction from back 
to front, and the lower posterior corners of the 
carapace form, therefore, as in the preceding species, 
on each side, a narrow rounded lobe which covers 
the sides of the metasome and extends almost to the 
commencement of the urosome. The frontal plate 
(see Pl. IV, figs. 9, 10) is well developed and of very 
narrow linguiform shape, pretty strongly arched 
above, and furnished at the extremity with a 
pointed spiniform prominence which forms the contin- 
uation of a carnia that runs along the lower 
side. The last segment of the metasome has, as in 
the preceding species, a pair of small rounded 
epimera, and are, as well as the 3 succeeding caudal 
segments, coarsely serrated on the posterior edge. 
The caudal rami are somewhat shorter than the 
2 preceding segments taken together, otherwise of 
perfectly the same structure ‘as in the preceding 
species. 
The eyes (see Pl. IV, figs. 9, 11) distinguish 
themselves in a high degree by their small size and 
rudimentary character, and only project a little for- 
ward from the carapace; for which reason they 
may easily be overlooked. They are, as in N. bipes, 
covered above with a squamiform plate running 
