5. PREPARING WHOLE SPECIMENS 33 



5. PREPARING WHOLE SPECIMENS 



Whole specimens, like skeletons, are easy to prepare, but are a little more 

 difficult to preserve than either skins or skeletons. After collection they 

 must be either kept in a solution or packed in such a way that they remain 

 moist, and they therefore tend to be both bulky and heavy. The liquids in 

 which they may be kept are of two different types, one being based on alcohol, 

 the other on formalin. Alcohol may be easier to obtain (if only in its more 

 drinkable form) in most parts of the world, but there may be local regulations 

 regarding its purchase and transport. It is very volatile and inflammable. 

 Formalin solutions have the advantage of being more inert, and can be 

 carried in a more concentrated form, but are less easily obtained, corrode 

 many metal containers, and produce unpleasant fumes. 



In the field the formalin method may be easier in that it involves only a 

 single solution, but this should not be put in a metal container and a glass or 

 plastic container with a top that can be fixed tightly in place is needed. 

 Alcohol prevents the decay of flesh but also gradually removes the water from 

 it and unless additional treatment is given may cause specimens to shrink 

 and harden over a period of time. It is necessary to inject a weak formalin 

 solution into specimens to "fix" the tissues before they are immersed in 

 alcohol, and for the proper treatment of alcohol specimens one will require 

 two bottles containing fixing solutions, plus a container with weak alcohol in 

 which specimens can remain for two or three days, plus a container with a 

 stronger alcohol solution for final preservation. 



In all cases a hypodermic syringe will be needed for injecting the specimens. 

 The best type for field use is one made of plastic rather than glass. The 

 needles are usually supplied with a fine wire for keeping the bore clear and a 

 watch should be kept during the injection of a specimen, since a number of 

 injections are needed for each bird and the needle may easily become blocked 

 with tissue. If this happens some parts may not receive the preserving fluid 

 and may subsequently deteriorate. 



Preparation of specimens 



1. In alcohol. For this a solution of 10% formalin (see appendix 1), and 

 a solution of 75 % glycerine and water are required for injection, together 

 with a weak solution of 10% alcohol in a container in which the specimens 

 can be immersed (see appendix 1 for preparation of solutions). The speci- 

 men is injected as soon as possible after collection. A hypodermic syringe is 

 filled with the formalin solution. Injections are made into the muscles of the 

 breast, legs, wings, and in large birds the muscles of the back as well. The 

 needles should be thrust well into the muscles and then drawn slightly back, 

 and the part being injected should be held lightly between the fingers. As 

 the plunger of the syringe is pressed down a slight distension of the muscle 

 can be felt as the fluid is injected. This enables the collector to check that 

 injection is occurring. Injections are also made into the abdominal cavity 

 via the belly, and into the thoracic cavity at the base of the neck in front. A 

 small injection is also made into the skull by pushing the needle up through 

 the roof of the mouth, from outside and below. 



The specimen is then left for ten minutes for the formalin to spread into 



