CRUSTACEA/ 
331 
mens found at Hongkong and England by so inucli as a variation 
that could be tortured into being of specific value. This^ more- 
over, appears frequently to be true of forms that We find de- 
scribed as specifically distinct ; but as yet no fortns have been 
determined by competent zoologists as specifically identical in 
both extreme zones, there being no intetmediate locality in 
Which they are known to exist. ^ 
This appears to be true of the species in question, the type of 
which we have seen, and from it the figure is taken that is given 
in the ^ Catalogue of Amphipodous Crustacea ^ for the British 
Museum. Prof. Lilljeborg states that, in the British Museum 
Catalogue of Amphipodous Crustacea, neither the descrip- 
tion iior the drawing is good^^ of this species — an assertion, 
considering that he had not seen the type specimen in the Mu- 
seum of the Jardin des Plantes, that rather argues a distinction 
between the arctic and antarctic specimens than that the figure 
in the catalogue is incorrect. The figure was originally drawn 
by an experienced artist for M. Lucas for M. Castelnau^s work, 
* Animaux nouveaux,^ &c. From a plate of this work, previ- 
ously to its publication, a tracing was taken^ then with the 
assistance of the original type specimen a close comparison was 
instituted, and some few, but small, corrections were tnade. The 
figure was afterwards seen both by Prof. Milne-Edwards and M* 
Lucas j so that we think that we are justified iti stating that the 
carcinologist may have confidence that the figure iti the British 
Museum Catalogue fairly and faithfully represents the general 
form of the type speeimen of Lysianassa magellanica. An 
opportunity for dissection was not available, as the speeimeii in 
the Museum was unique ; but we feel assured that both the short 
description and the figure may be depended upon, except perhaps 
that of one of the inferior antelmse, which was broken off when 
we saw it, at the second or third articulus of the fiagelliim, and 
which is so represented in the traeing from M. Lucases figure, 
but which, if our memory is not treaeherous, was aseertained by 
comparison with the same organ on the opposite side ; or it may 
have been hypothetieally inserted. The differenee between the 
figures of the arctic specimens as represented by Prof. Lillje- 
borg and that given of the antarctic specimen in the British 
Museum Catalogue is considerable. The cephalon is much 
longer, the pereion less deep, particularly near the centre of the 
animalj consequently, when extended, the arctic specimen is far 
less arcuate than that from the antarctic region. The superior 
antenii^ ate much longer, and carry a secondary appendage that 
itself reaches beyond that of the primary branch in L. magel- 
lanica. The first pait of gnathopoda are less robust and formed 
difFerently from that of the antarctic specimen. These several 
points of separation are too important, when taken in connexion 
with Prof. Lilljeborg’s deduction that no two specimens of the 
