There are known to be  at least six distinct styles of cloth and one style of wooden hats for the regular sized white clowns. 
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Plain printed

Early hats were designed to cover a plain head. They were made using two separate pieces of cloth. The hat was attached to the head with three small tacks. This one was custom designed for the "sunburst" suit pattern.

Felt with rim

This clown was fitted with a white felt hat. Its rim is turned up and overcast. Note that this clown's hat is offset.

 
The felt hat also came in red.

Felt, no rim

A version of the felt hat but without the turned up rim is shown on this early clown. This hat style was also used on monkeys of the same time. These felt hats are from ca 1910.

Gold rickrack

This early hat style was made from two pieces of cloth. A hat rim of gold rickrack was sewn to the rim. This is the silk cloth hat.

Wooden

The wooden hat is relatively rare on the regular sized clown. It was painted white with red dots and a red rim.

Woven cloth rim

This hat style was one of those designed to cover the wood cone. It was made with a single piece of cloth to which was attached a stitched- on woven cloth rim. The hat was attached to the wood cone with a little adhesive.

Overcast rim and gold rickrack

Like other overcast rimmed hats, this one was designed to cover a wood cone. Just above the rim a small gold rickrack strip was applied. These were used on clowns with silk suits.

Overcast rim

One-part head clowns were usually dressed with a cloth hat with an overcastting stitch around the hat's edge. The overcastting stitch was sometimes applied with a heavy stitch as shown here or a thin stitch pattern. The cloth is one-piece sewn along one side.