No. 5 (1921) 



MADRAS AQUARIUM 



69 



in the Adyar and the Fort moat as in the great irrigation tanks in 

 Kurnool, away in the heart of Southern India. The female lays 

 her eggs on the under sides of stones and logs; both male and 

 female keep guard over the eggs till hatched, the male showing 

 special solicitude. The Pearl-spot attains a foot in length and being 

 largely vegetarian in diet and non-predaceous, is being used 

 extensively by the Fisheries Department in improving inland 

 waters by introducing it into tanks where it was previously 

 unknown. It breeds both in salt and fresh water. 



An interesting account of the breeding habits of this fish will 

 be found in Vol. XII of the Madras Fisheries Bulletin, where 

 Mr. N. P. Panikkar describes them in much detail. 



Those Etroplus that live in fresh water are far paler in colour 

 than those that live in estuaries ; indeed the degree to which the 

 bands are darkened is a fair index of the degree of salinity of the 

 water where they live. 



The pretty Spotted Spsdc-fish, Scatopliagus argiis (Tam. Sippili), 

 so named ((trgus) from the rows of eye-like spots scattered over its 

 silvery sides, is usually present in this tank, together with other of 

 the many kinds related to the butterfly-fishes, all of which have 

 the peculiarity of being flattened from side to side like the pomfret. 



Fig. 5. — Spotted Spade-fish {Sc itoph,igtis ar.;iis). 



Another inhabitant is Cirrhitichthys aureus, called 5/7;/^'-^;/ by our 

 fishermen. It is a small fish, rose-tinted in faint longitudinal lines 



