COMMON VIPER. 71 
some, with lighter or darker spots, in others almost wholly 
black. 
The tendency of this species to vary in its colours has 
occasioned an erroneous multiplication of species by various 
authors. Some of the more remarkable and conspicuous 
varieties I proceed to describe. 
The first is the Red Viper (V. communis, var. B of 
Mr. Jenyns), described by my venerable friend the late 
Rey. Thomas Rackett, in the twelfth volume of the Lin- 
nean Transactions. It was found by him in Cranbourne 
Chase in Dorsetshire, in which county I have also obtained 
it from Poole Heath. It varies much in the brightness 
and intensity of its colour. 
