METHODS OF EXCHANGE. 85 



as well as in other transactions, but in addition you 

 want scientific honesty so that you may trust that 

 your man will not invent eggs to fit names you are 

 seeking, or names to fit eggs he would like to get rid 

 of. "A shade of suspicion, " as Dr. Coues remarks, 

 "is often attached to dealers' eggs, — not necessarily 

 implying bad faith or even negligence on the dealer's 

 part, but from the nature of the case." Doubt, from 

 any source, is inadmissible in the commerce of 

 natural history. 



STANDARDS FOR EXCHANGING. 



How shall an exchange be conducted ? On a cash 

 basis or species for species ? 



The best law, no doubt, is the Golden Rule, for 

 the advantage of both parties. Friends who can 

 meet and talk it over can arrange a "trade" without 

 difficulty. Among strangers, negotiating by corre- 

 spondence, the matter becomes more complex. In 

 the city of Brooklyn, and elsewhere, I believe, clubs 

 have been formed for the purposes of mutual inter- 

 change. These clubs fix an arbitrary cash value to 

 every egg — say a robin's egg shall be worth five 

 cents and a golden eagle's egg five dollars. On the 

 basis of this valuation, which may or may not rep- 

 resent the market price of each egg, all exchanges 



