274 
ZOOLOGY OF THE FAR EAST. 
Family ATYIDAE. 
Genus Caridina, Milne-Edwards. 
All the species recorded below possess epipods at the base of the first four 
peraeopods and a gill-formula which is apparently the same as that given for the genus 
by Caiman and Bouvier.' 
Caridina propinqua, de Man. 
igo8. Caridina propinqua . de Man, Rec. Ind. Mas., II, p. 227, pi. xix, figs. 6, 6a-f. 
1913. Caridina propinqua, Bouvier, Trans. Linn. Soc. Zool. (2), XV, p. 463. 
1915. Caridina propinqua, Kemp, Mem. Ind. Mus., V, p. 309. 
The specimens agree closely with those from the neighbourhood of Calcutta. In 
young individuals the rostrum extends little, if at all, beyond the end of the basal 
segment of the antennular peduncle, whereas in adults it almost or quite reaches the 
end of the second segment. On the upper border there are from 11 to 20 teeth,^ of 
which from 2 to 4 (usually 3 or 4) are situated on the carapace. On the lower border 
there are from o to 4 teeth (usually 2). 
The carpus of the first peraeopods is from 2 '8 to 3-2 times as long as broad. In 
the third pair the propodus is from 27 to 3-2 times the length of the dactylus ; the latter 
segment is slender and is armed with 6 or 7 spines, the terminal claw included. The 
propodus of the fifth peraeopod is from 2-4 to 2 8 times the length of the dactylus, the 
latter segment bearing from 43 to 55 spinules. There are from 11 to 16 movable spines 
on the outer uropod. 
The eggs are from 0 64 mm. in length by 0 39 mm. in breadth, when freshly ex- 
truded, to 070 mm. in length by 0 44 mm. in breadth, when on the point of hatching. 
Ovigerous females vary greatly in size, being from 12 to 20 mm. in total length. 
Dr. Annandale found Caridina propinqua in abundance in the Tale Sap in January 
and February, 191 6. It occurred among weeds in all parts of the lake, both in the 
inner portion where the water is in all probability fresh throughout the year and in the 
outer lake near the island of Koh Yaw in water of low salinity. There are also numer- 
ous specimens in the collection from the Patani River, below the town of Patani in 
the Siamese Malay States. The water in this locality, though fresh at the time the 
specimens were obtained, is subject to tidal influence. 
1 Bouvier, Ann. Sci. France Belgique. XXXIX, p 68 (1905). 
2 In fifty specimens the numbers of rostral teeth are as follows: — 
Dorsal teeth. Ventral teeth. 
2 specimens have 1 1 teeth. i specimen has no tooth. 
3 ., 12 ,, ' 6 specimens have i ,, 
2 ,, 13 ,, ! 30 ,,2 teeth. 
7 M ,, 14 ,, j 12 ,, ,, 3 
8 ,, >. 15 ,, j I specimen has 4 ,, 
8 16 ,, 
9 M ,, 17 
6 ,, „ 18 
3 „ 19 
2 .. ,,20 ,, 
