What does "Dried Herring" mean in "Romeo and Juliet?"?

ithout his roe, like a dried herring. O flesh, flesh, how art thou fishified! Now is he for the numbers that Petrarch flowed in. Laura to his lady was but a kitchen-wench— marry, she had a better love to berhyme her—Dido a dowdy, Cleopatra a gypsy, Helen and Hero hildings and harlots, Thisbe a grey eye or so, but not to the purpose.— Signior Romeo, bonjour! There’s a French salutation to your French slop. You gave us the counterfeit fairly last night.