EELATKMSHIPS WITH THE ELOEAS OF OTHEE EEGIONS. 



233 



Mexican and Central- American Genera and Species, with one exception, only 

 extending to the Galapagos outside of America. 



Orders. 



Genera and Species. 



Distribution. 



Burseraceae 



Leguminosae 



Bursera. 



„ graveolens. 

 Dalea 



Two endemic species. 



Also W. trop. Africa. 



Probably introduced ; not in early 



= Acrolasia squaJida, Hook. f. ? 



Island only. 

 Also widely colonized in India. 

 One endemic species. 

 One, or more, endemic, species. 



55 55 JJ 55 



Two endemic species. 

 Near T. ovalifolium, 03rst. 



One endemic species. 



One endemic species. 

 ? 



15 •>■> • 55 



collections. 

 Cbarles 



Acacia tortuosa. 



Conocarpus erecta 



Cupbea. 



Mentzelia. 



,, aspera . 



LoasacesB 



Tumeraceae 



Elaterium cordatum 



Opuntia 



Cucurbitaceae 



CactaceaB 



Eicoideae 



Cereus 



Mollugo verticillata. 



Elvira 



CompositaB 



Apocynaceae 



AcanthaceaB 



Vallesia glabra. 

 Tetramerium 



Labiatae 



Hyptis capitata. 

 Salvia occidentalis. 



„ tiliaefolia. 



„ micrantha. 

 Boerbaavia birsuta. 

 Pieuropetalum 



Nyctaginese 



Amarantaceae 



Orcbideas 



Pbyllantbus carolinensis. 







This short list is exceedingly interesting as showing a westward extension of the 

 American flora. Some of the plants named may be of recent introduction through 

 human agency ; but the bulk of them may be regarded as indigenous in the sense of 

 having reached the islands independently of man. Such a direct relationship to the 

 American flora does not exist in any of the other Pacific Islands. Traces of it are 

 found here and there. For instance, of the otherwise Andine genus Osteomeles there 

 is one species in the Pacific Islands, ranging from Pitcairn Island and the Sandwich 

 Islands to Maingaia and the Bonin Islands, or through nearly ninety degrees of longi- 

 tude. In Pitcairn Island it is associated with such littoral plants as Morinda citrifolia, 

 Guettarda speciosa, and Cerbera odollam, and the characteristic Australasian genus 

 Metrosideros. The highly differentiated flora of the Sandwich group contains an 

 element more remotely though not less certainly connected with the American, asso- 

 ciated with an Australasian element largely preponderating in individuals, especially of 

 a species of Metrosideros, a phyllodineous Acacia, and a Cyathodes. 



