"Take the prisoner downstairs", said Tom condescendingly.

by Mark Israel
 
     [This is a fast-access FAQ excerpt.]
A sentence where a description of the manner of saying refers
punningly to quoted matter is called a "Tom Swifty".  (Some
people restrict "Tom Swifty" to sentences where the pun is in an
adverb, and use "croaker" for sentences where the pun is in the
verb:  "'I'm dying', he croaked.")  The name "Tom Swifty" derives
from the Tom Swift adventure series for boys (whose enthusiastic use
of adverbs modifying "said" they parody); but the form goes back to
the 19th century, and was used by James Joyce in Ulysses (1922).
   I maintain the Canonical Collection of Tom Swifties, with over
900 entries.  It's available on the WWW as: [...]    
or by e-mail from me.
     [Mark Israel's Web site at Scripps apparently no longer 
     exists; however there is a Web site that apparently has 
     the same content, including his collection of Tom Swifties.
     The Web site is at
     <http://www.ccp14.ac.uk/ccp/web-mirrors/xtalview-mcree/pub/dem-web/misrael/>.
     To see the Tom Swifties, click on 'TomSwifties.html'.]      
   A sentence where words following a quotation humorously
reinterpret what is quoted ("'Eureka!' said Archimedes to the
skunk") is called a "wellerism", after the character Sam Weller in
Dickens' novel The Pickwick Papers.  The form predates Dickens.