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Phüomedes (Ph.) globosa.
All the specimens of this species dealt with below. mature females and males as well
as larvae, were collected during the Swedish Greenland Expedition, 1899,
all on the same occasion, the lTthof July, and at the same place, lat. 74n 10’ N., long 20°8* W.,
depth 2;5—40 m. It seems to me certain that they all really belong to this species, partly for
morphologica! reasons and partly because at the locality in question probably only this species
of this genus is found. Cf. this species in the special part below.
Six free-living larval stages could be distinguished.
General description o f the larval stages: —
Stage T: —
Male: As has already been pointed out by preceding authors (cf. the special part of
this work), this differs strikingly from the mature male. Shell: Average length, 2,4 mm.
It agrees entirely with the shell of the mature female. The first antenna, the m a
n-d i b 1 e, the maxilla and the f i f t h, s i x t h and s e v e n t h 1 i m b s are also of the
same type as those of the mature female; the posterior limbs have perhaps a somewhat smaller
number of bristles. Second antenna: The protopodite and exopodite have the same
appearance as in the mature female, but the bristles on the four distal joints of the exopodite
are primarily short and without natatory hairs; for the endopodite see the figure of this
organ of this species in the special part below. The furca has eight claws, which decrease
fa irly uniformly in length and strength the more proximallv they are situated. The lateral
e v e s are almost of the same size as in the mature male, but are only very slightly pigmented.
F ema le: This agrees completely with the male of this genus except in the
sexual character s, the endopodite of the second antenna and the lateral
ey es; in the latter characters it resembles the mature female, but is more larval in type.
Stage 11 : —
Male: Shell: Average length, 1,9 mm. The endopodite of the second antenna
is considerably smaller and much less differentiated than in Stage I; its second joint has
onlv two bristles. The posterior limbs have somewhat fe wer bristles and the lateral
e y e s are considerably smaller than in the preceding stage. The fure a has eight claws.
Otherwise this stage agrees with Stage I.
F ema le: This agrees completely with the male of this stage except in the sexual
characters, the endopodite of the second antenna and the lateral eves; in the latter characters
it resembles the female of Stage I, but is more larval in type.
In the following larval stages I did not succeed in distinguishing with certainty between
males and females by means of dissection.
Stage III: — Shell: Average length, 1,5 mm. In this stage too all the limbs are
present. The se vent h li mb, however, is only represented by a long, unjointed, up ward
point-ing appendage, which is quite without bristles. Sixth li mb: The end joint is furnished
ventrally with only about eight bristles. O t h e r li m b s are also furnished with fewer bristles than
in the preceding stages, but, like the sixth limb, they have about the definitive type. Each
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