454 STELLA B. VINCENT 



Lashley (18) gives us a note on the persistence of an instinct 

 and Hahn (8) a popular account of the hibernation of certain 

 animals. Among them are the bear, woodchuck and ground 

 squirrel. 



Amphibians. — The only article on the instinctive behavior of 

 amphibians is that of Banta (1) who gives some interesting 

 notes and careful observations of the mating behavior of wood 

 frogs which he watched at Cut off Pond, Cold Springs Harbor. 



Birds. — To observe the very first performance of the social 

 activities of an adult one must rear the animal in isolation and 

 then allow it, while under close observation, to come in contact 

 with another animal. Craig (5) does this and gives an inter- 

 esting account of the behavior of three male doves which he has 

 thus brought up apart from their fellows. He concludes, among 

 other things, that display behavior needs social stimulation; 

 that the motor aspect of the sexual reaction is definitely provided 

 for by inheritance but that what he calls the 'sensory inlet' is 

 not complete and is supplemented by experience; and that one 

 finds surprise, hesitation and even fear in the first performance 

 of an instinctive act while ease, skill and intelligent adaptation 

 are the gift of experience. 



Another paper which deals with sexual reactions also is that 

 of Huxley (13). He recounts in elaborate detail the very dra- 

 matic courtship or love habits of the Grebe. After describing 

 the bird and giving its animal history, he turns to the real interest 

 of the stud}^ — the relation of the sexes, (a) in the act of pairing, 

 (b) courtship, (c) nest building, (d) the relation of different 

 pairs, (e) other activities. In the discussion which follows, the 

 author tries to explain what he calls the facultative reversal of 

 the sexes in the act of pairing — a subject which is interesting 

 many investigators at the present time — and he then elaborates 

 a modification of the sexual selection theory which he calls 

 mutual selection. He says, " Where combined courtship actions 

 exist and a variation in the direction of bright color or strange 

 structure occurred it would make the actions more exciting and 

 enjoyable and those birds which showed the new variation first 

 would pair up first and peg out their 'territories' for nesting 

 before the others could get mates." * * * As to the courtship 

 activities he says, " These actions are much too elaborate and 



