172 STUDIES IN GEOLOGY, No. 4 



approaches closely to Pisonia eocenica Ettingshausen 17 which 

 is a common form in the Oligocene and Miocene of Europe. 



The number of fossil forms of Pisonia now known is con- 

 siderable. The genus appears in the Upper Cretaceous of 

 both North America and Europe. There are three well 

 marked species in the lower Eocene and one in the upper 

 Eocene of southeastern North America. In Europe there are 

 two Oligocene and four Miocene species and there is an 

 American lower Miocene form found in Florida. 



The existing species are numerous and occur in all the 

 tropics. Pisonia aculeata is a strand plant but most of the 

 species are largely represented in forests of the monsoon 

 type. Pisonia hirtella H.B.K. ranges from Mexico to north- 

 ern Argentina, others occur in Colombia. South of Ecuador 

 the genus is confined to the region east of the Andes. The 

 Eupisonia section of the genus, comprising shrubs and trees 

 with elliptical coriaceous leaves, is largely developed in the 

 Guiana highlands and in Brazil, Pisonia nitida Martius, laxi- 

 flora Martius, etc. The Pisllypampa fossil very probably 

 represents this section of the genus. 



Order RANALES 



Family ANONACE^ 



Genus ANONA Linne 



Anona cochabambensis Berry, sp. nov. 



PLATE VIII Fig. 4 



Leaves of medium size, ovate in general outline, with a 

 rounded base and a cuspidate apex. Margins entire, full and 

 evenly rounded. Texture subcoriaceous. Length about 10 

 cm. Maximum width, in the lower half of the leaf, about 

 4.1 cm. Midrib stout, prominent on the under side of the 

 leaf. Secondaries stout, regularly spaced, diverging from 

 the midrib at wide angles, pursuing straight, subparallel 



17 Ettingshausen, C., Tertiarflora von Haering, p. 43, pi. n, figs. 

 1-22, 1855. 



