THE ART OF PRESERVING BIRDS. 27 



bill horizontal with the back or bottom of the rounded 

 space, with the culmen (Plate IV., Fig. 1, d) nearly touch- 

 ing the paper. The skin must remain in this position 

 without being disturbed until perfectly dry, which in very 

 warm weather, with small birds, will be in about twenty- 

 four hours. 



If this corrugated board cannot be procured, the skin 

 may be placed on its back upon a flat surface, with a 

 little cotton on each side of it to prevent its getting dis- 

 placed. This is what is technically termed "a skin" 

 (Fig. 3), and this method of making them is the best I 

 have ever seen practised, and one that I have used for 

 years as being the most expedient. The skins so made 

 are less liable to injury, being stronger than some others, 

 and are also very easily mounted. I have made in a 

 single day, in the manner described, fifty skins, and with 

 practice almost any one will be able to do the same ; ten 

 minutes being ample time for each, including the meas- 

 uring. 



Before the skin is placed upon the board, it should be 

 labelled (Fig. 3, g) with a number corresponding to the 

 one placed upon the slip of paper containing the meas- 

 urements, etc., marked also for the sex of the bird, which 

 is done by using for the male the sign of the planet 

 Mars, thus $ ; for the female the sign of the planet 

 Venus is used, thus 9 . These signs are used by natural- 

 ists throughout the scientific world, and it is best to be- 

 come accustomed to them. 



Determining the Sex. — The sex of the bird is determined, 

 not by the plumage, which will sometimes set the student 

 at fault by its changes, and should never be trusted in de- 

 termining the sex, but by dissection, as follows : Take the 

 body of the bird after it has been ' removed, and cut with 

 the scalpel through the ribs (Plate X. A) on the sides 

 of the abdomen, thereby exposing the intestines; raise 



