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Relation lo Ph.(Pli.)
laevipes Daday.
J‘h. laevipes =
Pli. CharcoliDaday?
Relation to Ph. ( Ph.)
orbicularis Brady.
Remarks: — It is impossible to decide for certain, whether this species is identical with
Ph. (Ph.) laevipes, though it does not seem impossible. As a preliminary I considered it best
to describe it as a new species. The description of Ph. laevipes that is fourni in E. von Daday,
1908, p. 12 is exceedingly deficient, clearly drawn up without the author having the necessary
knowledge of the forms belonging to this sub-genus.
In passing 1 may point out that Ph. laevipes is probably a larva of the species Ph.
Charcoli, which is described by E. von Daday in the same treatise. Daday himself indicates the
possibility of these two forms being identical. Thus we read on p. 15 of this treatise: „En
général, les particularités de l’organism rappellent beaucoup la Phüomedes Charcoli, et, si la
structure des pattes vermiformes ne différait pas autant, on pourrait réunir les deux espèces,
vu que toutes deux sont du même endroit ,,(la côte de l’île Booth-Wandel, Terre de Graham,
Antarctis)“, encore que capturées à des dates différentes.“ According to this author the seventh
limb of Ph. laevipes is, unlike that of Ph. Charcoti, quite bare. This character to which Daday
attached such great importance that he derived the name of the species from it, can, of course,
not be regard ed as any reason for not identifying these species. It is known that this absence
of armature on the seventh limb is a character of the larva; all species of this genus seem to
have a seventh limb of this type during the third larval stage. Other characters as well, such
as the length of the shell, the number of furcal claws, etc. support the idea that Ph. laevipes is
a larva of Ph. Charcoti in the third stage.
The form dealt with by me here seems to differ from Ph. Charcoti, of which only the male
is described, in at least one character, namely the number of bristles on the seventh limb. Ph.
Charcoti is said to have only thirteen bristles, six on one side and seven on the other, while Ph.
(Ph.) rotunda is characterized, as we have seen above, by having a somewhat larger number
(23-26).
Another species to which Ph. rotunda is certainly very closely related is Ph. ( Ph.)
orbicularis— which, curiously enough and certainly ineorrectly, is regarded by its author, G. S. BRADY,
as a Southern variety of Ph. ( Ph.) globosa — „It is in all respects very similar to the well-known
European species P. Prenda" (globosa) „and may perhaps be fairly looked upon as a Southern
variation of that form“. G. 8. Brady’s description is unfortunately too incomplete to permit
of a certain identification. The relatively great length of the shell (2,5 mm.) and the faet that
„the surface of the shell is smooth and densely clothed with a villous coating of very short hairs“
(G. S. BRADY, 1907, p. 4) seem, however, to argue against the identity of these forms. It is,
however, not impossible that they are identical, nor can it be considered impossible that G. W.
MÜLLER was right when in 1912 he identified Ph. orbicularis with Ph. laevipes.
Habitat: — South Georgia: S. A. E„ Station 18, mouth of the W est Fiord,
Cumberland Bay, lat. 54" 15’S., long. 36° 25’ W.; 22. IV. 1902; depth, 250 m.; loose clay; temperature
at the bottom + 1,2° C: 1 mature female; R. M. S. 136. S. A. E., Station 22, off May Bay,
lat. 54° 17’ S., long. 36" 28’ W. (type locality); 14. V. 1902; depth, 75 m.; clay with
scattered algae; temperature at the bottom -f- 1,5° C: 1 mature female; R. M. S„ on slides.
S. A. E., Station 23, off the mouth of Morän Fiord, lat. 54" 23’ S., long. 36" 26’ W.; 16. V. 1902;
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