160 
og jog liar on Ticl vrevot i Tvivl om de ikke maaske kunde 
vsere Hanner af foregaaende Art. De skiller sig imidler- 
tid. soiu det vil sees, ikke blot i Folernes Bygning, men 
ogsaa i enkelte andre Ckaracterer. som ikke pleier at vsere 
modificerede Uos Hannerne (f. Ex. den tydeligt kjolede Bag- 
krop, Formen af de 2 bagre Fodpar og Halevedhamgene), 
hvorfor jeg foretrtekker indtil videre at beskrive dem som 
tilhorende en selvstamdig Art. 
Beskrivelse. Legemets Form er (se PI. XIII, Fig. 
6) i det vmseutlige som hos foregaaende Art, dog noget 
mere sammertrykt fra Siderne, mod inindre bred Rvg og 
forholdsvis lavcre Epimerer. 
Hovedet er som hos foregaaende Art oventil temmelig 
staerkt hvmlvet og Pandepladon forholdsvis kort og bred. 
Bagkroppon visor oventil i liele sin Laingde en meget 
tydeligt markeret Lrengdekjol, der dog bagtil bliver afbrudt 
ved et dyht Indsnit mellem 4de og sidste Segment. Side- 
pladerne paa 3die Segment er som hos H. abyssi bagtil 
stumpt tilrundede. 
0ine mangier ogsaa her fuldstmndigt, 
Folerne (Fig. 6 a og b) er srerdeles robuste og i hoi 
Grad udmmrkede derved, at Skaftet paa begge foruden de 
smdvanligc Burster viser paa den indre Side en sserdeles 
tat Besietning af eiendommelige fine Oilier, der i sin Byg- 
ning narmest synes at svare til de hos andre Amphipoder 
alone til lste Pars Svohe indskramkede klare Sandseborster. 
Disse Oilier er grupperede i tatte kostformige Knipper og 
rager delvis from foran Folernes forreste Kanter. Bisvoben 
paa lste Par er kjendeligt kortere end Hovedsvoben, og 
Svoben paa 2det Par synes forholdsvis mindre end hos fore- 
gaaende Art. 
De 2 forreste Fodpar (Fig. 6 c) har Haanden noget 
mere forlsenget og det Griberanden bagtil begrmndsende 
Hjorne stump ere. 
De 3 folgende Fodpar viser ikke nogen bemserkelig 
Forskjel fra samme hos foregaaende Art. 
6te Fodpar (se Fig. 6) er forholdsvis endnu noget 
stserkere forlamget end hos H. abyssi, og dets yderste Led 
er her kun hesat med korte og spredte Torner. 
Sidste Fodpar (Fig. 6 d) er temmelig uligt samme 
hos foregaaende Art, idet Hofteleddet er storre og mere 
regelmsessigt afrundet, med den bagre Rand ganske jevnt 
buet og den forreste lige, uden det strerke vinkelformige 
Fremspring nedentil, som udmserker dette Fodpar hos H. 
abyssi. 
Sidste Par Halefedder (Fig. 6 c) skiller sig ligeledes 
meget vsesentligt fra samme hos foregaaende Art. De er 
forholdsvis hetydelig st 0 rre, og Endegrenene er af en eien- 
dommelig membra nos Beskaffenhed, lancetdannede ogiKan- 
terne besatte med nogle meget smaa og spredte Haar. 
I was some time in doubt, whether they might not after all 
be males of the preceding species. Meanwhile, they differ, 
as will appear, not only in the structure of the antenna, 
but likewise in divers other characters, not usually found 
modified in the males (for example, the distinctly keeled 
posterior division of the body, the form of the 2 posterior 
pairs of legs and of the telson); and hence I have, for the 
present, seen fit to record the animal as a separate species. 
Description. — Form of the body (see PL XIII, 
fig. 6) essentially similar to that in the preceding species, 
though much more compressed from the sides, with the 
back less broad and relatively smaller epimera. 
The head, as in the preceding species, rather promi- 
nently arched above, and the frontal plate comparatively 
short and broad. 
The posterior division of the body exhibits above, 
throughout its entire length, a very distinctly marked lon- 
gitudinal carina, which, however, posteriorly, is severed by 
a deep incision between the 4tli and terminal segments. 
The lateral plates on the 3rd segment are, as in H. abyssi, 
obtusely rounded posteriorly. 
Eyes in this form, too. entirely wanting. 
The antennae (figs. 6 a, b) are exceedingly robust, 
and very prominently characterized by the peduncle on each 
pair, apart from the usual bristles, exhibiting along the inner 
side an exceedingly dense clothing of peculiar, delicate cilia 
which, in their structure, would seem to approximate closest 
the translucent sensory bristles exclusively confined in other 
Amphipods to the flagellum of the 1st pair. These cilia 
are grouped in close-set, scopiform fascicles, and project in 
part beyond the anterior margins of the antenna*. The sec- 
ondary flagellum on the 1st pair is appreciably shorter than 
the principal flagellum; and the flagellum on the 2nd pair 
would seem to be relatively smaller than in the preceding 
species. 
The 2 anterior pairs of legs (fig. 6 c) have the hand 
a trifle more elongate and the corner posteriorly defining 
the palmar margin obtuser. 
The 3 succeeding pairs of legs do not exhibit any 
appreciable difference from those pairs in the preceding 
species. 
The 6th pair of legs (see fig. 6) are relatively still 
more elongate than in H. abyssi, and the outermost ar- 
ticulation of this pair is furnished merely with short and 
scattered spines. 
The last pair of legs (fig. 6 d) are rather unlike that 
pair in the preceding species, the basal joint being larger 
and more regularly rounded, with the posterior margin uni- 
formly arched and the anterior straight, without the strong 
angular projection below distinguishing the said pair of 
legs in H. abyssi. 
The Inst pair of caudal stylets (fig. 6 e) differ likewise 
essentially from those in the preceding species. They are 
relatively much larger, and the terminal branches, lanceolate 
in form, exhibit a peculiar membranous structure having along i 
the margins a few exceedingly minute and scattered hairs. 
i 
