"Pennis" doesn't appear in my Latin dictionaries. "Penna" or "pinna" means "feather", but I don't see how "pennis" could be derived from "penna". If Dall intended "pennis" as a variant of "penis", then you should know that the word meant "tail" to the Romans, and the extension of its meaning to the "male member" is apparently another fossilized joke or euphemism. Does our resident lexicographer wish to <ahem> rise to the occasion by elucidating this mystery? Incidentally, pinna "feather" is also the source for "pen"; quill pens were once made from large feathers. The large bivalve Pinna "pen shell" was named by the Romans; Cicero used the word. Andrew K. Rindsberg Geological Survey of Alabama