The 1849/6 Half Dime is a controversial variety. Some experts, such as the authors of the CherryPickers' Guide, believe the traditional 1849/6 variety (FS-302) is actually an 1849/8. Less convincing is FS-301, which is a tossup as to whether it is an 1849/8 or an 1849/6. Walter Breen confused the issue further by listing FS-301 as an 1849/8/6 and FS-302 as an 1849/48.
Either way, there is a clear undertype on both varieties, and they are both very popular and highly collectible varieties.