Crustacea Decapoda and Stomatopoda. 
273 
(v) In the second peraeopods the chela is equal in length with the merus and is 
only about two-thirds as long as the carpus. In P. varians the chela is decidedly 
longer than the merus and only a little shorter than the carpus. 
(vi) The dactylus of the last three peraeopods is a little longer ; that of the third 
pair is about half as long as the propodus in P. sinensis, rather less in P. varians. 
(vii) There are more setae (9 or 10) at the apex of the telson. 
In other respects the two species appear to be in close agreement. 
The teeth on the upper border of the rostrum vary in number from 4 to 6, ' the 
hindmost being placed on the carapace behind the level of the orbit. On the lower 
margin there are from i to 3 teeth. 
On the ciliated margins of the antennules and buccal appendages there are 
numerous small cysts of a Protozoan apparently identical with that described by 
Sollaud. 
Sixteen specimens of Palaemonetes sinensis were obtained by Dr. Annandale in the 
vicinity of Shanghai in small ponds and ditches of fresh water. They were found in 
the month of October in company with Caridina and young Leander modesius : none 
of the females carry eggs.^ 
Family ALPHEIDAE. 
Genus Alphcus, Fabricius. 
Alpheus paludicola, Kemp. 
1915. Alpheus paludicola, Kemp, Mem. Ind. Mus., V, p. 303, pi. xiii, figs. 11-13. 
The only difference I am able to detect between specimens collected by Dr. Annan- 
dale in lyower Siam and those originally described from the Chilka Lake in Orissa is 
that the rostrum is very slender and rather longer, extending considerably beyond the 
end of the orbital hoods. In the form of the chelae and in all other particulars there 
is precise agreement. The eggs are 13 or i"4 mm. in diameter. 
According to Dr. Annandale' s notes the specimens differed somewhat in colour 
from those observed in the Chilka Lake, the transverse bands of pigment on the 
abdomen being missing. They were translucent, without definite markings, but tinged, 
owing to the presence of scattered chromatophores, with reddish brown. The eyes 
were black and the palm and fingers of both chelae were deeply tinged with blue, 
especially on the dorsal surface. The eggs were pale green. 
The specimens were obtained in the Tale Sap, in the channel connecting the upper 
and lower lakes at a depth of 3^ to 8 metres. They were found in a shallow layer of 
dense mud overlying a coarse sandy bottom and occurred in company with Upogebia 
heterocheir. The specific gravity of the water in the channel was variable according to 
the state of the tide, but probably does not rise much above 1-004. 
Alpheus paludicola has hitherto been found only in the Chilka Lake on the 
Orissa coast of India. 
1 Of sixteen specimens five have 4 dorsal teeth, tea have 5 and one has 6. 
2 Of sixteen specimens seven have i inferior tooth, eight have 2 teeth and one has 3. 
3 See Addendum, p. 207. 
