How to Distinguish a Mouse From a (Small) Rat

My apology for asking a very elementary question, which has puzzled me
on and off for years but a satisfactory answer has always escaped me.
How can one tell at a glance a mouse from a rat? Suppose I catch a
glimpse of a dark coloured, small rodent of about the length of the
index finger, not including the tail, running along a short skirting
board then promptly disappearing round the corner of the room. Without
going into the finer morphological differences between the two, which
are perhaps useful only when the rodent is stationary (and preferably
with the other kind put alongside for ease of comparison), are there any
gross distinguishing features between a (not fully grown) rat and a
mouse?

Thank you in advance.

Bee.
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[I have found my Shangri-La in ntlworld.]


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J&S Bouchard wrote:
> Bee wrote:
> > ...are there any gross distinguishing features between a (not fully
> > grown) rat and a mouse?
> Where is this rat or mouse?...And if there's one baby rat, there
> should be more baby rats...



Thank you for the response, Joanne. No, that was only a hypothetical
situation; I have never seen one in my house. The one occasion I did
see one was in a low-cost housing estate. Come to think of it, that
rodent probably was a rat, because it was large.

Bee.
--
[I have found my Shangri-La in ntlworld.]


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