42 



A REMARKABLE CASE OF 

 '^PARENTAL" CARE IN THE GENUS COTTUS. 



By ALEXANDER MEEK. 



In April this year (1915) it was found that a Cottus had laid 

 eggs in one of our tanks, and that a small Cottus had mounted 

 guard over them. It was presumed that the eggs had been laid 

 by one of two large Cottus, and that the specimen which watched 

 them so assiduously was a male. An attempt was made to obtain 

 a picture of the mass of eggs and the guardian, but they were too 

 awkwardly placed, and both were removed to a glass vessel for the 

 purpose. But this spoilt the charm entirely. In the confined new 

 quarters the Cottus would not look at the eggs, and I have made 

 an attempt in the figure reproduced here to give an indication of 

 one of the usual positions assumed by the guardian. 



A closer examination was now made of the Cottoids concerned. 

 They consisted of the two large specimens, which we found to be 

 mature sjDcnt females of Cottus scorjnus, and the one which had 

 guarded the eggs, and it turned out to be an immature female 

 Cottus bubalis. The presumption is then, and it is supported by 

 the evidence of the Laboratory attendant, that the eggs were laid 

 by one of the Cottus scorjnus, and that the immature female Cottus 

 bubalis at once assumed the position of guardian. She was fre- 

 quently found supporting herself on her pectoral fins between the 

 glass and the wall of the tank, with the eggs just in front of her 

 head. Whether she was there or in some other part of the tank 

 when an object^ such as a net or brush, was introduced, she at once 

 swam out at it, and placed herself between the object and the eggs, 

 and in every way behaved in the manner so common in the males 

 of species of fish which lay demersal eggs. 



From further enquiries it appears that both the Cottus scorpius 

 sjjawned in the tank in which they had remained during the winter, 

 and that the Cottus bubalis was introduced before the second mass 

 of eggs was laid. It need not be said that both masses were unfer- 



