I9I4-] SOUTHEASTERN NORTH AMERICA. 171 



odeae are large and occur on all of the continents, with monotypic 

 genera in Xorth America (Isomeris), South America (Stubelia 

 Atamisquca, Bclcnciia), Africa (Pteropetalum, Cladostcmon) , and 

 Australia (Rocperia, ApophyUum). The subfamily Dipterygioideae 

 has a single genus with only five or six species of Nubia, Arabia and 

 the Punjab. The subfamily Roydsioldeae includes about a dozen spe- 

 cies, the genera Roydsia and Stixis being confined to India and the 

 genus Forchhammeria being Mexican. The subfamily Emblingioi- 

 deae has only a single genus and species confined to Western Aus- 

 tralia. No far-reaching conclusions regarding origin or past history 

 can be deduced from our present knowledge of the geographical dis- 

 tribution of the Capparidaceae and the fossil record is so imperfect 

 that very little can be said regarding this history. 



The following are the only fossil records known to me : F. von 

 Miiller has described somewhat uncertainly determined fruits from 

 the Tertiary of Australia as the genera Dieune and Plesiocapparis. 

 The latter has two species and is considered as probably a member 

 of the section Busbeckia of the genus Capparis. Schenk has de- 

 scribed the petrified wood of another form from the Tertiary of 

 Egypt under the name Capparidoxylon. The genus Capparis has 

 furnished a well-marked Wilcox species very close to the existing 

 Antillean tree Capparis domingcnsis Sprengel. There are about one 

 hundred existing species of Capparis, mostly tropical, and although 

 found in the Eastern Hemisphere the majority occur in the Ameri- 

 can tropics, especially in Central and South America. The oldest 

 known fossil forms are two species described by me as species of 

 Capparites from the Upper Cretaceous of Alabama (Tuscaloosa 

 formation). In addition to the Wilcox species previously mentioned, 

 Engelhardt has described a Tertiary species from Bolivia. Many 

 years ago Unger described a third species from the Middle Miocene 

 of Styria but Schimper considers the latter to be a papilionaceous 

 form. While the fossil record of Capparis is so meager such facts 

 as are available would seem to indicate that it originated in the 

 American Upper Cretaceous. Very many of the modern forms are 

 shrubs or small trees of the strand flora and such is believed to have 

 been the habitat of the Wilcox species. 



