1. Fifty four species of Laurales, subdivided to 15 genus and 3 families, were under study. 2. Detailed description and differences in structure between species were emphasized. 3. Based on the observation of the author, several facts of significance were mentioned as follows: (1) The genus Machilus was not likely to be included in the genus Persea. (2) There was no significant difference between the two cultivarities of genus Persea i.e. Persea americana and Persea drymifolia. (3) Machilus arisanensis was not likely to be included in Machilus acuminatissima. (4) Machilus Pseudo-longifolia was not likely to be included in Machilus Zoihoensis. (5) As the structuae of Litsea dolichocarpa lay between those of Litsea and Actinodaphne, it was more likely that these two genera should be combined into one.