438 
ZOOLOGY OF THE FAR EAST. 
This element ma}^ be regarded as a relict fauna and among the Amphipoda is 
represented by Monoculodes limnophilus, a representative of an almost exclusively 
Arctic genus, and one hitherto known from^ only strictly marine localities. 
The marine element in the fauna of the Tai-Hu suggests a comparatively recent 
geological origin for this water-system. 
The freshwater systems of Japan are of more remote origin and the crustacean 
fauna provides evidence of affinities with that of the Palaearctic region of Europe 
and Asia, with America and with Australasia, that is, with the older and more remote, 
both in time and space, freshwater faunas of the globe. 
Among the Isopoda I have already called attention to the occurrence of Asellus 
aquaticiis in L- Biwa, a Palaearctic species of wide distribution, and of Caecidothea 
kawamurai, a new species from a well in Otsu near Kyoto, whose nearest allies are 
found in caves and freshwater wells in America. 
Among the Amphipoda there are corresponding relationships. In one of the 
inland mountain streams of Japan was discovered Gammarus piilex, a Palaearctic 
species with a distribution corresponding to that of Asellus aquaticus. This species 
was, however, absent from L. Biwa, its place being taken by a new species, Gamma- 
rus annandalei, allied to the freshwater species of the great inland waters of the 
Palaearctic region (such as the Caspian Sea and T.ake Baikal), of America (especially 
to the species G. ramellus) and of Australia. 
In one of the other mountain streams of Japan Dr. Annandale discovered a 
species of Atyloides which is very closely allied to two freshwater species of the 
genus found by Sayce in Victoria, Australia. This discovery provides among the 
Amphipoda, a precisely parallel case to that already known among the Macrura in 
the genus Paratya { = Xiphocaridina) . 
The results obtained by Dr. Annandale from the point of view of geographical 
distribution are thus of exceptional interest. 
I desire to thank Dr. Annandale for giving me the opportunity of examining 
and reporting upon this interesting collection, and m)^ wife for the drawings illustrat- 
ing this report. 
ISOPODA. 
Tribe FLABELLIFERA . 
Family ANTHURIDAE. 
Genus Cyathura, Norm, and Stebb. 
Cyathura carinata (Kroyer) ? 
[PI. XVIII, figs. 1-9. J 
Locality.— Tai-Ru, a little N.E. of Si Dong Ding, China, 2-xii-i5, 3 metres, on a 
bottom of mud with a little decayed vegetation, one female, 10 mm. 
Remarks. — The element of doubt in the identification of this specimen is due to the 
appearance of the telson. This is very short, not much more than half the length of 
the uropods and very much shorter than in any other member of the family known 
