On Endosperm in Dicotyledons

1. Statistical analysis of available data on the types of endosperm and of vessel perforation in dicotyledonous taxa indicates that (a) Nuclear-type endosperm is positively associated with porous perforation and that (b) Cellular-type endosperm is negatively associated with such perforation. 2. As it has been well established that porous perforation of the vessel member represents a high degree of phylogenetic specialization, it follows that Nuclear-type endosperm is in all probability more advanced than Cellular-type endosperm.