(5973 
XXXI. On the Use of the Pedes scansorii of Birds; in a Letter to 
the Rev. William Kirby, F.R.S. and L.S. By the Rev. Revett 
Sheppard, F.L.S. 
Read June 16, 1818. 
| Mx pear Sin, 
Ha»rrrsixo a few days since to take up Ray's Wisdom of God 
in the Works of the Creation, I was particularly struck with the 
passage where, speaking of the Woodpecker tribe, he says, “ Their 
toes stand two forwards, two backwards; which disposition (as 
Aldrovandus well notes) Nature, or rather the wisdom of the Cre- 
ator, hath granted to Woodpeckers, because it is very convenient 
for the climbing of trees.” | 
The attempt to prove this assertion, adopted by so many and 
able naturalists, to be altogether unfounded, must appear to sa- 
vour of presumption in one who has so little of the philosopher 
about him: nevertheless, I hope to convince you that such dis- 
position of the toes in the Woodpecker tribe was intended by the 
Author of Nature for a very different, though equally wise pur- 
pose. I know of but six genera, viz. Psittacus, Cuculus, Picus, 
Ramphastos, Trogon, Bucco, that are furnished pedibus scansorus, 
i.e. with two toes before and two behind ; and of this number I am 
acquainted with the manners of the three first only. 
To begin with Cuculus :—I speak only of our common species : 
Here is a bird furnished with two toes before and two behind, and 
yet is actually never known to climb at all; a convincing proof 
that such conformation does not necessarily bring with it the power 
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