Previous work is updated with the inclusion of data on the 15 sungrazing comets that appear to have been detected by the Solwind and SMM coronagraphs during 1979-1989. These objects are almost certainly Kreutz sungrazers, and the SMM objects belong a defined Subgroup I. A case is made for the association of the Solwind objects with this subgroup. It is shown that there is a prevailing direction to the orbital evolution, with nodal longitudes tending to increase and perihelion distances to decrease with time. Genetic relations are indicated and/or confirmed for various members of the comet group. It appears that all the observed Kreutz sungrazers originated in one or the other of two comets that must have appeared around the year 1100.