84 



MADRAS FISHERIES BULLETIN 



VOL. XIV, 



aquarium. They are ever on the watch for the attendant with his 

 pail of fish. His coming is sensed long before he reaches their tank 

 and this is sufficient to throw them into a state of wild excitement. 

 Other curious but by no means beautiful fishes in this tank are 

 several kinds of Cat-fishes belonging usually to the genera Plotosiis 

 and Ariiis (Tarn. Kelcthi)- They get their English name from the 

 long whisker-like feelers arranged around the mouth. The family 

 is a large one, with numerous representatives both in the sea and 

 in rivers and tanks. The skin is smooth and scaleless. Cat-fishes 

 have considerable value as food. Certain species, as Ariiis, are 

 met with in the sea in great shoals and single captures may run 

 into thousands. On the Malabar Coast cooked cat-fish heads, 

 highly spiced and salted, are sometimes served free to customers 

 by toddy-shopkeepers to create a greater thirst ! 



Fig. 17.— a common Cal-ihh {Plo^os//s cam'i/s). 



The dorsal and pectoral fins are often armed with formidable 

 spines capable of inflicting severe wounds if trodden on or incau- 

 tiously handled. In some cases a poisonous secretion is introduced 

 into the wound and causes considerable inflammation. As with 

 the tail spine of rays, so here the fishermen are accustomed to 

 break off these spines before taking the fish to market. 



The male of certain species of Ariiis has the curious habit of 

 receiving the eggs, as extruded by the female, into his mouth where 

 he retains them till the young hatch out. As the eggs are 

 particularly large, about half an inch in diameter, the number that 

 he can care for is limiteti. As the eggs completely fill his mouth, 

 the poor father has to abstain from feeding till his family are 

 born, and able to swim away. What part the unincumbered 

 mother takes during this time is obscure ; possibly she devotes her 

 attention to piscine politics ! 



Many fishes change colour in synipathy with their environ- 

 ment or when excited. One of the best examples is the case of a 



