Ron Guth: The popularity of the 1857 Flying Eagle Cent proved conclusively the concept of the Small Cent. After 1857, the Large Cent was discontinued and the Mint turned out Small Cents in record numbers in 1858, this time topping 24 million coins. Three major varieties appear on 1858 Small Cents: Small Letters, Large Letters, and 1858 over 7. On the Small Letters variety, the A and M of AMERICA are completely separated; on the Large Letters variety, the A and M are connected at their bases.
Based on the PCGS Population Report, the Large Letters variety appears to be the most common (the Small Letters has a population that is 58% lower than that of the Large Letters). In Mint State, the most frequently-seen grade for the Small Letters variety is MS-64, followed by MS-63. The finest examples of the Small Letters 1858 Flying Eagle Cent are nine MS-66s.