Organic Conjiection Between Pliysical and Psychical 261 



Mexicanus, and the Califurnia tuwlicc, Pipilo fimciis, may be 

 specially mentioned in tills connection. The fact that do- 

 mesticated song birds, like the canary, may be brouglit to 

 sing almost perpetually is only an extreme manifestation 

 of tendency among song birds to sing in excess of any strict 

 utility of song. 



Think of tlie monotonous repetition in the croaking of 

 frogs, the chirping of crickets, the stridulations of cicadas, 

 and so on ! I have counted more than five hundred con- 

 secutive chirps of a cricket in about half an hour, with 

 only a little variation as to notes or intervals. And tliis is 

 surely a very moderate example of what actually occurs — 

 as any one can easily convince himself by listening and count- 

 ing almost any still night, almost anywhere where crickets 

 live. Probably the chirping of crickets is employed in mat- 

 ing. Very well. But are the thousands of cliirps uttered 

 by a given individual each niglit for many nights, the small- 

 est number upon which the species can survive .^^ Even ask- 

 ing of the question reveals the monstrosity of a theory that 

 would necessitate an affirmative answer to it — as strict ad- 

 herence to the natural selectionist meaning of utility un- 

 doubtedly would. 



In place of bringing forward additional instances, which 

 could easily be done, to show that vocal sounds and bodily 

 performances of various sorts more or less obviously con- 

 nected with mating among higher animals are produced in 

 excess of what the strict application of the rule of physio- 

 logical economy would dictate, I shall do no more than util- 

 ize the conclusions of two investigators who seem specially 

 qualified to speak on the subject, and assume that these con- 

 clusions would receive the sanction of all zoologists who have 

 given serious attention to the matter and have formed their 

 judgments unbiased in favor of any explanatory theory. 



The first of these investigators is W. II. Hudson, who 

 represents a period a little antecedent to the present spc- 



