78 



FIELD ORNITHOLOGY 



the cheek-muscles soon tire, and the operator hecomes "blown" 

 himself before long. The operation had better be done over 

 a basin of water, both to receive the contents, and to catch the 

 egg if it slip from the fingers. The membrane lining the shell 



. R\ 



Fig. 7.— Hooks for extracting 

 embryos, nat. size ; after New- 

 ton, a, &, c, plain hooks ; (2, 

 bill-hook, having cutting edge 

 along the concavity. 



Fig. 6. — Scissors, knives, and forceps, J nat. size ; 

 after Newton. 



should be removed if possible. It 

 may be seized by the edge around 

 the hole, with the forceps, and drawn 

 out, or picked out with a bent pin. 

 But this is scarcely to be accomp- 

 lished in the case of fresh eggs, when 

 the membrane may be simply pared 

 smoothly around the edge of the hole. Eggs that have been incubated 

 of course offer difficulty, in proportion to the size of the embryo. The 



supposed to be a very modern trick ; but it dates back at least to 1828, when M. 

 Danger proposed "a new metliod of preparing and preserving eggs for the cabinet," 

 which is practically the one now followed, though he used a three-edged needle to 

 prick the hole, instead of our modern drill, and did not appear to know some of our 

 ways of managing the embryo. I make this reference to his article to call attention 

 to one of the tools he recommends, which I think would prove useful, as being better 

 than the fingers for holding an egg during drilling and blowing. The simple instru- 

 ment will be understood from a glance at the figure given in the NuttaU Bulletin, iii. 

 1878, p. 191. The oval rings are covered with a light fabric, as mosquito-nettuig or 

 muslin, and do not touch the egg, which is held lightly but securely in the netting. 

 The cost would be trifling, and danger might be avoided by Danger's method. 



