I58 MADRAS FISHERIES BULLETIN VOL. XII, 



of algse. This species is noted for its elegance of movement and 

 tameable habits ; it is well suited for stocking tanks and lakes, 

 owing to its fair size, palatability, hardihood and non-predaceous 

 nature. 



Although both species are quite common in the maritime 

 regions of the Madras Presidency and of Ceylon, very few 

 investigators seem to have paid much attention to them. Dr. 

 A. Willey (7) has published observations upon the breeding habits 

 of E. suratensis. Thomas (6) and Sundara Raj (5) have also given 

 a number of facts concerning both of them. The note which 

 follows is a contribution to a fuller knowledge of their reproduction 

 and life-history. 



1. ETROPLUS SURATENSIS (Block). 



Malayalam — Karimeen - Black-fish. 

 Habits and characteristics. 



Nest making. — During the breeding season the fish resort in 

 pairs to shallow shady places and make a search for a suitable 

 object upon which to deposit the eggs. Stones, pieces of wood, 

 coconut husks, or midribs of coconut leaves, submerged at a depth 

 of not more than three feet of water, are preferred. If the surface 

 selected is smooth as is the outer rind of coconut husk, it is made 

 rough by biting on it in order to raise short fibres. After select- 

 ing the object one side of it is made clean by biting away all 

 dirt or vegetable growth. If the object is found not to be raised 

 sufficiently from the ground to afford convenience for the spawning 

 movements, a broad cup-like excavation is made in the ground 

 just below the surface selected by taking the mud and sand in the 

 mouth and blowing them away. Although each of the pair takes 

 part in the preparation of this simple nest, the male is found to 

 attend to it more particularly. The pair spend three to five days 

 in selecting the place and in preparing it for the reception of 

 the ova. 



Egg laying. — The female lies flat in the cavity or space adjacent 

 to the surface prepared and gently moves from one side to the 

 other attaching the ova one by one in a single layer. In doing so the 

 urino-genital papilla, here so elongated as to deserve to be termed 

 an "ovipositor," is placed in contact with the surface, and the 

 black ventral fins are brought together to press on it gently to help 

 the extrusion of the egg. After five or six such operations she 



