abstracts: botany 401 



east. Lithologic variations within the marine beds are due to local 

 differential uplifts which occurred during Tertiary time, and which 

 formed long island ridges in the sea which then covered the present 

 Coast Ranges. These Tertiary differential uplifts also served to com- 

 plicate the structural features of the region. The present Coast Ranges 

 are made up of a series of long northwestward trending ridges, the indi- 

 vidual ranges of the system, separated by wide valleys. These ranges 

 and valleys are of structural origin, having been formed by the pro- 

 nounced folding and faulting of early Pleistocene time. The structure 

 resulting from the comparatively recent folding is superimposed upon 

 structures formed by similar earlier movements. An interesting result 

 of this combination of structures is that, although the general trend of 

 the major lines of structure produced by the earlier movements was 

 northwest, and thus parallel to the later structure, the blocks subjected 

 to differential uplift during the earlier part of the Tertiary were not 

 always the same as those most recently uplifted. An area which 

 formed a range during the Tertiary and from which many thousand feet 

 of beds were eroded may now form the bottom of a structural valley, 

 and another area which was a structural trough during parts of the 

 Tertiary may now form a recently uplifted range. W. A. E. 



BOTANY. — Studies of Tropical American 'phanerogams — No. 2. Paul 

 C. Standley. Contributions from the U. S. National Herbarium, 

 18: 87-142. 1916. 

 The paper consists of descriptions of new species and of taxonomic 

 notes upon various groups of plants, chiefly the Amaranthaceae, Alli- 

 oniaceae, Malvaceae, and Rubiaceae, and the association of families 

 formerly known as the Leguminosae. Most of the new species are 

 based upon material obtained in Panama by Mr. Henry Pittier. A 

 large number of species published in the genus Pisonia are transferred 

 to Torrubia. A new genus of the Malvaceae, Wercklea, based upon a 

 showy-flowered tree of Costa Rica, is published jointly with Mr. Pit- 

 tier. Peltaea, a new genus of Malvaceae, embracing 4 species, is pro- 

 posed and Lopimia, of the same family, is restored. There are included 

 descriptions of three new species of persimmons (Diospyros) from Mex- 

 ico, and 11 species of Psychotria from Panama. Two genera of Rubia- 

 ceae, Cassupa and Stachyarrhena, are reported from North America 

 for the first time. P. C. S. 



