Ancient Roman religious practices: a correction

Marcus Aurelius sacrificingI received an email from a former student with the promising subject line “entrails.” It reads:

You mentioned in your post on Originalism class 4 that Roman priests would examine bird entrails in preparation for great political events. Actually, a Roman haruspex would examine the entrails (usually the liver) of any particular sacrificial animal, which could have been poultry if the offeror was poor, but was most commonly sheep. An augur’s method of divination, by contrast, involved watching the skies and interpreting the birds’ flight paths– most famously, when Romulus and Remus determined that Rome was to be founded on the Palatine hill rather than the Aventine when Romulus saw twelve auspicious birds in the sky, while Remus saw only six.

In one of his lesser known letters, Cicero told of an augur who complained that haruspices lacked empathy. A haruspex who overheard the comment angrily dismissed augury as “legalistic argle-bargle.”