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part of Nembutal. Prepare only small quantities as the solution soon loses 
its strength. Small lizards and snakes require only a few drops, but large 
snakes (over two feet) and turtles will require one cc or more. 
‘Chlorotone,’ the commercial name for Hydrous Chlorobutanal, may be 
used for killing amphibians by drowning them in it. A few crystals to a 
quart of water makes a suitable killing solution. 
Ethyl alcohol, diluted to 10 per cent may also be used in the same 
manner. Specimens should be removed as soon as they die. 
Procaine Hydrochloride may be injected into reptiles and amphibians to 
kill them (Livezey, 1958). A 10 per cent solution is made by dissolving tablets 
of the drug in water. Each tablet contains 0.07 gm. It may also be obtained 
in crystalline form or in a prepared 1 and 2 per cent solution. Most reptiles 
will be killed by an injection near the heart of 0.05 cc ( = 0.47 mgm) per gram 
of body weight. Amphibians may be killed by drowning in the solution as 
well as by injection. 
Measurements 
Although specimens are not usually measured before preservation in 
herpetological studies, this procedure is strongly urged here whenever 
practicable. Too often inaccurate measurements are obtained from speci- 
mens which have been preserved for varying lengths of time. This is due to 
distortion and/or shrinkage of specimens in preservative. Careful measure- 
ments of fresh, relaxed specimens, taken immediately after they have been 
killed, are infinitely more valuable. All measurements should be recorded in 
millimetres. The length of most Canadian frogs, salamanders, and small 
lizards may be taken with a 152-mm rule. Snakes, large lizards, and very 
large frogs and salamanders will require a tape measure. Leg length (tibia) 
for frogs may be taken with hand calipers. All measurements should be at 
least estimated to the nearest half millimetre. 
The following should be recorded : 
Snakes and Lizards and Salamanders — - 
(1) Body length— taken from the tip of the snout to the vent (posterior 
angle of vent in salamanders) along the underside of the body. 
(2) Total length — taken from the tip of the snout to the tip of the tail. 
Frogs — 
(1) Body length — taken from tip of snout to centre of the vent by 
placing the ruler along the midline of the back. 
(2) Tibia length — taken from ‘knee’ to ‘heel’ of the hind foot when it 
is flexed. 
Turtles — 
Carapace and plastron length and width, taken at widest portions. 
(This is a point-to-point straight line measurement with calipers — 
never along the curve of the shell.) 
Measurements may also be taken of the length of the head and neck — 
with the neck extended — from the tip of the snout to the junction 
of neck and body, and the length of the tail — from the tip of the tail 
to the vent, and from the tip of the tail to the junction of the tail 
and body. 
