Searching the web, I discovered that what I thought was a parish in the Civil Registration Index is actually a registration district. For the part of Cornwall I was searching, there are about a dozen parishes in the St. Austell registration district, including the parish of Tywardreath. So if you use this index, you may need to know the name of the district that includes the parish. I found a map of the district under the Cornwall page on a UK web site from Cyndi's list. Hope that helps. Cyndi's list has connections to thousands of genealogical web sites. http://www.cyndislist.com