TROnCAL AMERICAN RUBIACE.12 323 



occur in tliis area. Of tliese, the following are peculiar to 

 it : Pinchieya, Houstonia, Kelloggia, Mitchella, Crusea, and 

 Didymcea. The following have migrated, so to speak, from the 

 warmer areas, wliere they are principally represented : Exosteiiima, 

 Lindenia, Hamelia, Geniim, Cliiococca, Mitracarp2C7}i, Bichard- 

 sonia, Bclhiinium. The next group of genera are essentially 

 West Indian, rock-dwelling marine plants ; they occur elsewhere 

 only on the opposite coast of southern Florida : CateshcEa, 

 Strumjjfia, Ernodea, Erithalis. The remainder of the genera in 

 this area are either cosmopolitan, like the Galiea?, or of general 

 occurrence in the warmer parts of the world ; such are CejjhalantJuis, 

 Oldenlandia, Bandia, Guettarda, Morinda, Psycliotria. 



(2) Central American area, including the warmer parts of 

 Mexico, and the remainder of Central America. Many of the 

 genera here are also met with in South America. Bouvardia is 

 an exception, as this occurs elsewhere only in North America. 

 These are peculiar to this area : Bavnia, Dej^j^ea, NotoiMehia, 

 Opliryococcus, Xerococcus, Asemnantka, and Placocarpa. The 

 recently-described Otocalyx, Plocaniophyllon, Stylosiplionia, and 

 Pinaroplnjllon were collected once in Mexico, by Purpus. 



(3) West Indies/'' — Out of about 60 Eubiaceous genera occur- 

 ring in this region, about twenty-five are found generally in the 

 American tropics, but not elsewhere ; nineteen or twenty are 

 endemic (many in Cuba) ; Portlandia and Lmdejiia have been 

 found only in the West Indies and Central America ; Lasiantlms 

 and Antirrhosa occur only in the Old World, outside the West 

 Indies. The remainder, apart from the Florida-genera mentioned 

 above, are the widespread forms referred to at the end of our 

 account of the Northern area. 



(4) Tropical South America, including Brasil. — This is the 

 heart of the whole region, with a w^onderfully rich flora, very 

 imperfectly known. Beside a considerable number confined ex- 

 clusively to this area, several genera which are most richly repre- 

 sented here have, we have already noticed, species in the previous 

 areas in the northerly direction ; many, too, are represented in the 

 opposite direction of Paraguay and the warmer parts of temperate 

 South America, now about to be considered. 



(5) Paraguay aiid Uruguay. — The flora of this area is inti- 

 mately associated with that of the neighbouring parts of Brasil. 

 The Eubiaceous genera number less than forty, and none, appa- 

 rently, are endemic. The following Brasilian genera, that are other- 

 wise unknown outside the tropics of South America occur : Sphinc- 

 tanthus, Coussarea, Declieuxia, Stcelia, Emmeorhiza. Alibertia, 

 Thieleodoxa, and Budgea are represented in the West Indies, but 

 not elsewhere outside South America. The other Paraguayan 

 genera are either such South American genera as have migrated 

 as far as Central America, Mexico, or even, in the case of Genipa 

 and Chiococca, as far as North America ; or, the widespread 

 genera already referred to (Galiea3, Psycliotria, etc.). 



* Not including Trinidad, which is regarded, for floristic purposes, as South 

 American. 



