of rime richissime spanning an entire verse. Alphonse Allais was a notable exponent of holorime. Here is an example of a holorime couplet from Marc Monnier: Classical French rhyme not only differs from English rhyme in its different treatment of onset consonants. It also treats coda consonants in a distinctive way. French spelling includes several final letters that are no longer pronounced, and that in many cases have never been pronounced. Such final unpronounced letters continue to affect rhyme according to the rules of Classical French versification. They are encountered in almost all of the pre-20th-century French verse texts, but these rhyming rules are almost never taken into account from the 20th century. The most important "silent" letter is the "mute e". In spoken French today, final "e" is, in some regional accents (in Paris for example), omitted after consonants; but in Classical French prosody, it was considered an integral part of the rhyme even when following the vowel. "Joue" could rhyme with "boue", but not with "trou". Rhyming words ending with this silent "e" were said to make up a "double rhyme", while words not ending with this silent "e" made up a "single rhyme". It was a principle of stanza-formation that single and double rhymes had to alternate in the stanza. Virtually all 17th-century French plays in verse alternate masculine and feminine couplets. The now-silent final consonants present a more complex case. They, too, were traditionally an integral part of the rhyme, such that "pont" rhymed with "vont" but not with "long". (The voicing of consonants was lost in liaison and thus ignored, so "pont" also rhymed with "rond".) There are a few rules that govern most word-final consonants in archaic French pronunciation: The distinction between voiced and unvoiced consonants is lost in the final position. Therefore, "d" and "t" (both pronounced /t/) rhyme. So too with "c", "g" and "q" (all /k/), "b" and "p" (both /p/), and "s", "x" and "z" (all /z/). Rhymes ending in /z/ are called "plural rhymes" because most plural nouns and adjectives end in "s" or "x". Nasal vowels rhyme whether spelled with "m" or "n" (e.g. "essaim" rhymes with "sain" but not with "saint"). If a word ends in a stop followed by "s", the stop is silent and ignored for purposes of rhyming (e.g. "temps" rhymes with "dents"). In the archaic orthography some of these silent stops are omitted