2 
EDMUND W. SINNOTT AND IRVING W. BAILEY 
palmate lobed (fig. 3), palmate compound^ (fig. 7), pinnate simple 
(fig. i), pinnate lobed (fig. 17) and pinnate compound (fig. 10). A 
brief survey of the distribution of these types throughout the three 
main growth forms of Dicotyledons (trees, shrubs and herbs) in 
various regions of the earth is set forth in the following table.^ 
It will be observed that in these modern floras the pinnate type 
is markedly predominant everywhere and that the simple pinnate 
condition alone constitutes from 60 per cent to 70 per cent of the 
species. Other noteworthy facts are the abundance of compound 
leaves in warm regions, the almost complete absence there of palmately 
lobed woody plants, and the practical confinement of the pinnately 
lobed type to herbaceous forms. 
In view of the preponderating evidence that woody Angiosperms 
are more ancient than herbacous ones,^ it seems probable that leaf 
^ Trifoliate leaves with stalked terminal leaflets (frequently called pinnately 
trifoliate) will be regarded in this paper as palmately compound. 
2 Analyses have been made of the following floras as to types of leaf or types 
of node or both: 
North America: Flora of the Northern United States and Canada, Britton and 
Brown; Flora of the Rocky Mountains, Coulter; Flora of the Florida Keys, Small; 
Flora of the British West Indian Islands, Grisebach; Flora Nicaraguensis, Goyena. 
South America: Flora Brasiliensis, Martius and others; Historia de Chili: 
Botanica, Gay; Report of the Princeton Expedition to Patagonia: Botany, Macloskie. 
Europe: English Botany, Sowerby; Flora des Ncrdostdeutschen Flachlands, 
Ascherson and Graebner; Flora Rossica, Ledebour; Flora des Alpes, Bouvier; 
Flora Espanola, Lazara; Flora Italica, Fiori and Paoletti. 
Asia: Flora Orientalis, Boissier; Flora of Syria, Palestine and Sinai, Post; 
Flora Simlensis, Collett; Flora of the Upper Gangetic Plain, Duthie; Flora of Bom- 
bay, Cooke; Handbook of the Flora of Ceylon, Trimen; Maylayan Flora, King; 
Flora van Nederlandesch Indie, Miquel; Flora Hongkongensis, Bentham; Flora of 
Manila, Merrill. 
Africa: Manual of the Flora of Egypt, Muschler; Flora of Tropical Africa, 
Oliver, Thiselton-Dyer and others; Flora Capensis, Harvey and Sonder, and 
others; Forests and Forest Flora of Cape Colony, Sims; Natal Plants, Wood; Plantes 
de Madagascar, Baillon and Castillo; Flora of Mauritius and the Seychelles, Baker. 
Australasia: Flora Australiensis, Bentham; New Zealand Flora, Cheeseman. 
Oceana: Flora of the Hawaiian Islands, Hillebrand; Indigenous Trees of the 
Hawaiian Islands, Rock. 
Analyses were also made of the genera of woody Dicotyledons enumerated in 
Engler and Prantl's Natiirliche Pflanzenfamilien; and of the species of trees and 
shrubs from China and Japan in the herbarium of the Arnold Arboretum. 
^ The Origin and Dispersal of Herbaceous Angiosperms. Sinnott, E. W .and 
Bailey, I. W., Annals of Botany, 28: Oct. 1914. 
