Reptile techniques

I have been looking through the book Natural Sciences Curator Patricia Francis lent me: Wagstaffe and Fidler’s The Preservation of Natural History Specimens.

The book details many techniques for preserving vertebrates, sometimes even by family! A few of the techniques are out of date, as various chemicals used in the past for preserving specimens are now illegal. Some have also fallen out of favour due to the bulkiness the technique entails. A method that was popular for casting large reptiles in the past was the Walters’ Plastic Method. This method involved the application of colours which, when bound up in the liquid plastic, are laid down in successive layers within a plaster mould. In this way the colours of a specimen can be reproduced. Reptile colour fades quite quickly after death.

However, if colour is not an issue, then the specimen can be preserved in alcohol. Since I want to learn more about how to preserve wet specimens, I was interested in this section on how to preserve Geckos and Skinks:

Preservation with alcohol-Preliminary Treatment Fixing

1. Slitting
a.)Small specimens- With a large scalpel or fine-pointed scissors make a longitudinal slit about 1/4-3 inches long according to size of specimen in ventral body wall.

b.)Medium sized specimens- As above, but remove through ventral slit any large masses of food, and also make small slits along ventral surface of tail, avoiding any region of vent, and small slits along side of tail and one immediately behind each thigh and upper arm.

2. Injecting– Inject thoroughly with a hypodermic syringe body cavity and tail of all specimens, except Geckos with 95 percent alcohol. Inject Geckos in the same manner, but if small with 75 percent alcohol and if large with 85 percent alcohol.

3. Setting– If time permits proceed from (i) to (iv) inclusive, otherwise place specimens in a dish of appropriate size as (i) and proceed from (iii) to (iv) inclusive.

(i)Place specimens in a dish of appropriate size.
(ii)Align head, body and tail of small and medium-sized specimens or if tail very long, coil or bend alongside body. Extend limbs to natural positions.
(iii)Cover Geckos with 65 percent alcohol and all other species with 85 percent alcohol; 95 percent alcohol is sometimes recommended for skinks.
(iv)Use a volume of fluid ten times greater than the volume of each specimen and leave to fix until specimens are reasonably hard and firm. Cover dish to prevent excessive evaporation and do not allow the preservative to drop much below the strengths indicated.

Source: Wagstaffe & Fidler: The Preservation of Natural History Specimens Volume Two. (1968) H.F. & G Witherby

Photo taken at the Natural History Museum, London, and is therefore copyright the NHM.

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