468 PROFESSOR CHARLES CHILTON ON THE 
and the first segment of the urus bears a well-marked triangular carina. The appendages 
are in close agreement with those of the type, and in both the inner lobe of the first 
maxilla bears four sete instead of two as given in the diagnosis of the genus in Das 
Tierreich Amphipoda, two of the setz being shorter than the others. 
While it is easy to identify the Scotea specimens with Mr Wa txker’s type, the 
position is not so clear if we try to go a little further. In the Southern Cross 
Amphipoda Mr Waker described another species, Tryphosa adarez, differing from 
T. murrayt in certain minor characters which appeared at the time to be of specific 
importance. In 1907, however, on the receipt of numerous other specimens from the 
Discovery Expedition, he united the two species under the name 7. murrayz, as the 
examination of the specimens showed that the characters at first relied upon were 
subject to variation. In this he was perhaps right, but a comparison of his specimens 
of 7. adare: with my specimens shows that they differ from them as they do from 
T. murray: in having the first gnathopod rather stouter towards the distal end, and 
particularly in having the carpus stouter and rather shorter than the propod, while in 7. 
murray? it is as long as or longer than the propod ; though the differences are not great, 
they appear to be constant in the specimens I have examined. Moreover, Mr Waker 
states that 7. adarez closely resembles 7. barbatipes Stebbing, but differs in the pro- 
portions of the joints of the upper antennze and of the gnathopoda. Before comparing 
the Scotia specimens with 7. murray: Walker I had also noted their great similarity 
to T. barbatipes, except in the shape of the first enathopods, and comparison of the three 
shows that 7. adarez is largely intermediate in this character between 7. murrayi and 
T. barbatipes, so that, if the first two are united, it will be necessary to unite them both 
with 7. barbatipes. This species is, however, now placed by SrEeBBiNG in another genus, 
Tryphosella, and the shape of the first gnathopod in the type specimen of 7. barbatepes ~ 
which I have also examined is considerably different from that of 7. murray, the 
carpus being shorter and the propod longer and stouter and slightly different in outline, 
as may be seen from an examination of the figure in the Challenger Report, and there 
are differences in some other characters. It is quite likely that an examination of 
specimens from other localities will show complete transitional forms, but at present I 
cannot go fully into this question, and in the meantime prefer to identify my specimens 
with 7. murray: and to leave that species distinct from 7. adare and from T, 
barbatipes. In all three species the side plates of the first and second gnathopoda 
have a small tooth at the posterior angle. It is to be hoped that a complete revision of 
this group will be made before long ; such a revision must, however, include the similar 
forms from northern seas, some of which appear to be very closely allied. 
Tryphosa murray is known from South Victoria Land and from near Coats Land, 
though not yet recorded from intermediate localities. 
