440 
ZOOLOGY OF THE FAR FAST. 
It is evident that more observation is required on the form and structure of the 
pleopods in this family but as far as present information goes the genus Gyathura 
would appear to be distinguished by having both rami of all the pleopods single- jointed^ 
the inner ramus in all cases branchial and without setae on its margins. 
The occurrence of this species in the fresh waters of the Tai-Hu is of remarkable 
interest. It was originally described from Greenland and is quite a common form in 
the shallow waters on the East Coast of the United States. It is also of frequent 
occurrence in the brackish waters of the Baltic Sea. Gurney has recently recorded 
it from the rivers of East Norfolk, and notes that "it seems to be capable of living 
in water either fresh or brackish. At Oulton Broad, at the time of capture, the water 
was ver}^ salt, but on the three other occasions on which it has been met with the 
water in which it was living was practically fresh." In the Tai-Hu, the vvater ac- 
cording to Annandale, is quite fresh. 
AMPHIPODA. 
Family OEDICKROTIDAE. 
Genus Monoculodes, Stimpson. 
Monoculodes limnophilus, n. sp. 
[PI. XVIII, figs. 10-20.] 
Localities. — China. 
1. Whangpoo River, between Shanghai and Wusung, 5-7 metres, io-xii-15^ 
abundant. 
2. From Walker Island, up Hsi Kon Bay, Tai-Hu, 2-3 metres, 5-xii-i5, 
abundant on a bottom of hard mud with shells in patches : no weeds. 
3. Walker Island, Tai-Hu, close in shore, 5-xii-i5, three specimens on mud with 
small stones and some weed. 
4. Tai-Hu, a little N.E. of Si Dong Ding, 3 metres, 2-xii-i5, thirty-three 
specimens. 
5. Off Mouth of Moo Too Creek, Tai-Hu, 3 metres, 2-xii-i5, one specimen. 
6. Tai-Hu, a little N.E. of Si Dong Ding, 3 metres, 2-xii-i5, abundant. 
(Types.) 
Description. — Body smooth and not carinated ; ornamented by a series of black 
chromatophores scattered over the back and sides, and on the posterior segments of 
the thorax and the anterior segm.ents of the pleon, arranged in a transverse band 
across the posterior part of the somites. 
Head (pi. XVIII, fig. 10) produced into a moderately long, acute and curved 
rostrum which extends to the distal end of the first joint of the peduncle of the first 
antenna. The head is not narrowly produced behind the eyes as in M. hanseni, M . 
kroyeri and M . longirostris. 
Eyes moderately large, contiguous, pigment black, a large mass of ramose black 
chromotophores situated dorsally over the eyes and almost masking them in dorsal 
view . 
