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at present to state, as they are both only known in the last larval stage. One
of the forms has already been recorded at an earlier date, whereas the other is
new. They are here simply designated
Cryptoniseid
(PI. C, fig. 2).
as No. 1 and No. 2.
No. 1.
Podascon (?) Stebbiugi, Giard & Bonnier.
Character*. Body comparatively robust, oblong oval in form, with the
greatest width rather behind the middle. Cephalic segment seinilunar, with the
frontal edge evenly curved ; anal segment angularly produced behind. Eyes want-
ing. Basal expansion of antennulse short and broad, with the posterior edge
divided into 8 short, and somewhat irregular, blunt teeth. Antennae rather
elongated, extending almost to the end of the 4th pedigerous segment, flagelluni
fully as long as the peduncle. Coxal plates distinctly pectinate. Legs of the
usual structure, dactylus of the posterior pairs bidentate at the tip. Uropoda
with the outer ramus very small, scarcely exceeding half the length of the inner,
both having the extremity simple, and tipped with 3 slender bristles, the middle of
which it the longest. Colour not yet determined. Length of body 1.70 mm. Found
occasionally in the incubatory pouch of Onesimus plautus, Kroyer.
Remarks. This form is undoubtedly identical with the parasite recorded,
but without any name, by the Rev. Th. Stebbing in his account of the Amphi-
poda of the Barents Expedition,
and for which MM. Giard and Bonnier have
proposed the name Podascon (?) titebbinyi. The specific name ought certainly to
be retained, as this form has been described and figured by that distinguished
author in a very recognizable manner; but, on the other hand, I regard
it as
very questionable, whether it can be adduced to the genus Podascon of MM. Giard
and Bonnier, or even to the family Podasconidce of those authors. We do not
know the last larval stage of either of the 2 species of the genus Podascon recor-
ded, and of course are not in a position to institute any comparison. Indeed,
the only motive for referring the present annimal to that genus is based upon
the fact that it has been found on an Amphipod, belonging, however, to a ra-
ther different genus. But, in my opinion, this coincidence is far from giving full
evidence of its true relationship. Thus, as above stated, we find in the mar-
supial cavity of Mysidse 2 very different types of Epicaridre belonging to quite
different families, viz. a Dajid (Dajus) and a Cryptoniseid (Asconiscus), and
moreover, not seldom a Choniostornatid, Nysidion, belonging even to quite a