The interest in the French dictionary (ok, boronia, dictionnaire--belated welcome, by the way) led me to try and find other words that are the same or very similar in both languages. One I put in was fiche. One of the def.'s was fiche dactyloscopique. I googled dactyloscope on a guess, and was led to dactyloscopy: n. comparison of fingerprints for identification. (From The Dictionary of Difficult Words.) Then, I found:
dactyl
n. metrical foot comprising one long followed by two short syllables; Zoology, digit. dactylate, a. like a finger. dactylic, a.; n. verse of dactyls.
Same dictionary:
http://www.tiscali.co.uk/reference/dictionaries/difficultwords/data/d0004218.html

My question: how did dactyl come to have these two seemingly unrelated meanings?