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



The telson resembles that of .4. erythraeus 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. 'jd). 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 japoniciis was described by Kishinouye from the Inland 

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

 are from the following localities : — 



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



^-|^ Kilakarai, Ramnad dist., S. India ... ,, Three. 



2-69_* Ennur backwater, near Madras ... N. Annandale. Three. 



9JLSi:9 Mergui Archipelago, n°i7'— 11'^28'N., 



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



Patani R., below town of Patani, Siamese 



Malay States ... ... ... N. Annandale. Six. 



Tale Sap, near Singgora, G. of Siam ... ,, Many. 



From market, Osaka, Japan ... ,, Many. 



Niigata, Japan ... ... ... ? Several. 



1 o 



96 9 1 



10 

 9692 



9693 

 1 O 



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 i"or65 (corrected), while at 

 Kilakarai it was obtained in pure sea water in the vicinit}" 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. 



