58 Records of the Indian Museum. [Vol. XIII, 1917.] 



The telson resembles that of .4. erythraeiis and A. indicus, but 

 the tip is rounded rather than pointed (text-fig. 5/). I have not 

 been able to detect the pair of small teeth mentioned by Kishinouye , 

 but the outer corners of the apex are sometimes a little angular. 



The external border of the outer uropod differs from that of 

 all the other three species in the complete absence of the tooth 

 between the ciliated and non-ciliated portions. In adults, more- 

 over, the latter part is a little longer than the former, the reverse 

 being the case in the other forms (text-fig. yd). In very young 

 specimens the proportions are rather different, the non-ciliated 

 part being equal to, or even a trifle longer than the ciliated part. 



Large specimens reach a length of about 26 mm. 



Acetes japonicus was described by Kishinouye from the Inland 

 Sea of Japan and from Korea. Specimens in the Indian Museum 

 are from the following localities : — 



'"^^^"'^ Mormugao Bay, Portuguese India ... S. Kemp. Many. 



^-5-§^ Kilakarai, Ramnad dist., S. India ... ,, Three. 



10 ' 



5A8_-i'. Ennur backwater, near Madras ... N. Annandale. Three. 



10 



sfiALis Mergui Archipelago, ii^ij'— ii°28'N., 



^° 98°29'— 98°36' E ... ... 'Investigator.' Several, 



9fi9" Patani R., below town of Patani, Siamese 

 ^° Malay States... 



SAIA. Tale Sap, near Singgora, G. of Siai 

 10 '^ °° 



^^-^ From market, Osaka, japan 

 Niigata, Japan ... 



10 



96 93 



N. Annandale. Six. 



Many. 

 Many. 

 ? Several. 



In the Patani river the species was found in fresh water, but 

 in a situation subject to tidal influence; in Mormugao Bay it was 

 taken in water of specific gravity 1-0165 (corrected), while at 

 Kilakarai it was obtained in pure sea water in the vicinity of a 

 coral reef. 



The species was found in the Mergui Archipelago and in the 

 Tale Sap in company with A. indicus, and in the Patani river with 

 A . erythraeus. 



The known distribution may be summarised as, — W, and S. 

 coasts of India, lower parts of Bay of Bengal, Gulf of Siam, Korea, 

 Japan. 



