756 Memoirs of the Indian Museum. [Vol. V, 



horizontal diameter of the eye is shorter than the length of the snout and is contained 4-3 

 times in the length of the head. The eyes are situated in the anterior half of the head and 

 are not visible from below. The mouth is small and the maxilla just reaches to below the 

 anterior margin of the orbit. The lower jaw is slightly the longer and is turned upwards. 

 The gill-openings extend on the under surface for a short distance. The preopercular 

 spine is curved and is turned downwards and forwards. There are 9 weak rays in the second 

 dorsal and 10 in the anal. 



In spirit the colour is reddish yellow with a large number of minute black dots scattered 

 all over the body. These dots are aggregated near the upper margin of the base of the 

 pectoral fin and on the whole of the caudal fin, rendering them dusky. The under surface of 

 the head and belly is somewhat whitish. 



Measurements in hundredths of the total length without the caudal fin. 



Total length excluding length of caudal ... ... ... 23-5 mm. 



Length of head ... ... ... ... ... ... 33-1 



Height of head near occiput ... ... ... ... ]8-2 



Width of head ... ... ... ... ... ... 22-1 



Length of snout ... ... ... ... ... 8-5 



Diameter of eye ... ... ... ... ... 7-6 



Interorbital width ... ... ... ... ... 5-5 



Length of caudal peduncle ... ... ... ... ... 30-6 



Height of caudal peduncle ... ... ... ... ... 13-6 



Longest ray of dorsal fin ... ... ... ... ... 14-8 



Longest ray of anal fin ... ... ... ... ... 15-3 



Length of pectoral fin ... ... ... ... ... 26-4 



Length of pelvic fin ... ... ... ... ... 17-1 



Length of caudal fin ... ... ... ... ... 22-1 



Genus BUTTS Bleeker. 



B litis butis (Ham. Buch.). 

 1876. Eleotris butis, Day, Fish. India I, p. 315, pi. lxvii, fig. 3. 



This species is represented by a single specimen in the Chilka Survey Collection. It 

 is 52 mm. in length without the caudal. It is known to occur in the seas and estuaries of 

 India and its range extends to the Malay Archipelago. 



Sub-family PERIOPHTHALMINAE. 



Genus PERIOPHTHALMUS Bloch & Schneider. 



Periophthalmus koelreuteri (Pallas). 

 There is only one specimen of this species, obtained near Manikpatna Island in March, 

 1914. It is 43 mm. in length without the caudal. The species is common on the coasts 

 of India and in estuaries and is said to ascend tidal rivers. 



