254 ANIMAL INTELLIGENCE. 



CHAPTEK IX. 



BATRACHIANS AND REPTILES. 



On the intelligence of frogs and toads very little has to 

 be said. Frogs seem to have definite ideas of locality; 

 for several of my correspondents inform me that they have 

 known cases in which these animals, after having been 

 removed for a distance of 200 or 300 yards from their 

 habitual haunts, returned to them again and again. This, 

 however, may I think perhaps be due to these haunts 

 having a moistness which the animals are able to perceive 

 at a great distance. But be this as it may, certainly the 

 distance at which frogs are able to perceive moisture is 

 surprising. Thus, for instance. Warden gives a case in 

 which a pond containing a number of frogs dried up, and 

 the frogs thereupon made straight for the nearest water, 

 although this was at a distance of eight kilometres.^ 



A curious special instinct is met with in the toad Bufo 

 ohstetricans, from which it derives its name ; for the male 

 here performs the function of an accoucheur to the female, 

 by severing from her body the gelatinous cord by which 

 the ova are attached. 



Another special instinct or habit manifested by toads 

 is described by M. Duchemin in a paper before the 

 Academy of Sciences at Paris.^ The habit consists in the 

 killing of carp by squatting on the head of the fish and 

 forcing the fore-feet into its eyes. Probably this habit 

 arises from sexual excitement on the part of the toads. 



I have one case, communicated to me by a corre- 

 spondent, of a frog which learnt to know her voice, and to 

 come when called. As fish will sometimes do the same 



■ * Account of the United States, vol. ii., p. 9, 

 2 April 11, 1870. 



