xxxii INTRODUCTION 



Incubated eggs, though almost at the point of hatching, are 

 made by experts into nearly perfect specimens. Following their 

 methods, drill the hole and then coat the shell with flexible collodion. 

 After removing a small part of the fluid, if the egg is small, insert 

 a solution of pepsin or of chlorinated soda, — Labarraque's solution, 

 — and let the egg stand for a few hours, after which blow out the 

 softened portion of the contents. Add more of the solution, and 

 let the eggs stand again, keeping on until you have emptied the 

 shell. Large eggs may be treated with a solution of caustic potash, 

 care being necessary not to allow the alkali to touch the shell. To 

 prevent accident it is well to have a basin of water near in which to 

 immerse the egg if necessary. The collodion is removed after the 

 completion of the work by the use of ether. 



Each set of eggs and each nest should be kept in a box, with a label 

 something like the following, from the Bendire and Ralph collection 

 in the National Museum : — 



A. 0. U. No. Scientific name, 



Private No. Common name, 



Collector, 



Locality, 



Date, No. of Eggs in Set, 



Identification, Incubation, 



Nest : Diameter, Depth,. 



Composed of 



Location,. 



Of whom and when received,. 



Nests should be kept in boxes to fit their size. Great care 

 should be taken to protect them from moths and other destructive 



