Studies of the Icacinaceae, II. Humirianthera, Leretia, Mappia, and Nothapodytes, valid genera of the Icacineae

With jour platesThe four genera considered here have been treated at various times and by various authors as one.They belong to that general group of the Icacineae having free petals which are pilose on the inside.This contribution is an attempt to clarify the problem by redefining the genera and by incorporating new lines of evidence taken from studies of the wood, pollen and fruits.Humirianthcra is a distinct genus.The limits of the remaining genera have been drawn in various manners.Baillon (Adansonia 3: 367.1862-3) considered them all as synonymous with Icacina.Bentham and Hooker (Gen.PI. 1:351.1862), Engler (Mart.Fl.Bras.12(2): 50.1872) and House (Amer.Midi.Xat.fJ: 62. 1922) have considered them under either Mapp'ia or Lcrctia.In Baehni's recent monograph the Mappia complex has been divided.The Old World species were placed in the newly proposed genus Neoleretia while the New World species were retained in the emended genus Mappia.Baehni acknowledged Mappia of Jacquin to be an invalid name; however^ since its predecessors are also invalid, he proposed the name be added to the list of nomina conscrvanda.Baehni, however, misinterpreted the genus Xothapodytes Blume, which other workers have shown to be made up of the Asiatic species of ''Mappia.'' Recently, Sleumer (Xotizbl.15: 247.1940) has rejected Baehni's genus Xcolcrctia and transferred most of the species to Xothapodytes.This appears to be the correct procedure.Applying strict priority Sleumer also rejected the name Mappia Jacq.as a later homonym and took up the name Leretia Veil, for the American species.Before his paper appeared, the name Mappia Jacq.had been published in the official supplementary list of additions to the nomina conscrvanda in the Kew Bull, for July 1940.Baehni and Sleumer have placed all the Xew World species of the Mappia complex in one genus.\\'ith this I do not agree.At least Lcrctia cordata (including L. Vcllozii, L. nitida, and L. Pocppigiana) cannot belong in the genus Mappia^ as differences are found in the wood, pollen grains^ fruits, and centers of distribution.The segregation of the Mappia complex accepted here is not new.Miers (Ann.Mag.Xat.Hist.II.9: 392.1852) and Engler (Xat.Pflanzenfam.III.5: 249.1893) have both considered Mappia and Leretia distinct.Baehni has pointed out the differences between the Old and X'ew World