A dictionary of Proverbs (Oxford Paperback Reference)

An APE’s an ape, a varlet’s a varlet, though they be clad in silk or scarlet
A varlet was formerly a menial servant, but the word also took on the sense of ‘scoundrel’ or ‘rogue’. Scarlet was the colour of the official or ceremonial dress of various dignitaries, including judges. Cf. LUCIAN Adversus Indoctum 4 ^I;i'" /7"'7u;<71 iian/.u, an
ape is an ape.. even if it has gold insignia; ERASMUS Adages I. vii. simia simia est, etiamsi aurea gestet insignia.

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  1539 R. TAVERNER tr. Erasmus’Adages 21 An ape is an ape although she weare badges of golde. 1659 J. HOWELL Proverbs (English) I An Ape’s an Ape, A Varlett’s a Varlett, Though they be cladd in silk, or scarlett. 1732 T. FULLER Gnomologia no. 6391 An Ape’s an Ape: a Varlet’s a Varlet, Tho’ they be clad in Silk or Scarlet. 1967 D. MORRIS Naked Ape i. The naked ape is in danger of..forgetting that beneath the surface gloss he is still very much a primate. (‘An ape’s an ape, a varlet’s a varlet, though they be clad in silk or scarlet.’) Even a space ape must urinate. ■ appearance, deceptive; nature and nurture
  

ape see also the HIGHER the monkey climbs the more he shows his tail.
appear see TALK of the Devil, and he is bound to appear.
APPEARANCES are deceptive
A common US form is appearances are deceiving.

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  1666 G. TORRIANO Italian Proverbs 12 Appearance oft deceives. 1784 in Collections of Massachusetts Hist. Society (1877) III. 186 The appearances in those mountainous regions are extremely deceptive. 1846 H. MELVILLE Typee xxiv. Appearances.. are deceptive. Little men are sometimes very potent, and rags sometimes cover very extensive pretensions. 1927 E. F. BENSON Lucia in London v. Mr. Merriall.. watched the three figures at Georgie’s door. ‘Appearances are deceptive,’ he said. ‘But isn’t that Olga Shuttleworth and Princess Isabel?’ 2002 A. VANNEMAN Sherlock Holmes and Giant Rat of Sumatra xviii. 128 ‘Why, Mr. Holmes, you are the most wide­awake man here.’ ‘Appearances are deceiving,’ returned Holmes. ■ appearance, deceptive; deception