168 THE VOYAGE OF ELKS. CHALLENGER, 



it as common on the sea-beach of nearly all the Fiji Islands ; and its area embraces the 

 Society and Marianne Islands. Nadeaud says it is a common shrub on most coral 

 islands ; but that it had become very rare in Tahiti, where it is destined to be extir- 

 pated. There are specimens in the Kew Herbarium from Ducie Island, collected by 

 Cuming and J. T. Arundel ; the latter says : " The commonest thing on all these low- 

 islands, generally growing by the sea, and sometimes quite large." There are also specimens 

 from the Ellice, Union, and Gilbert groups, collected by the Revs. J. Whitmee and T. 

 Powell, with memoranda to the effect that it is one of the characteristic features of the 

 vegetation; and from several small islands in the Indian Ocean, as Bird, Cerf, and Poivre 

 Islands. Several other species of the genus are littoral in tropical and subtropical regions, 

 both in America and the Old World. 



Tournefortia sarmentosa, Lam. 



Tournefortia sarmentosa, Lam. ; Benth., Fl. Austr., iv. p. 390; Miq., Fl. Ind. Bat., ii. p. 927 ; Dene., 

 Herb. Timor. Descr., p. 66. 



Aerou ; Ki ; Timor Latjt. — This species ranges from the Philippines to North Australia ; 

 it also occurs in the Mauritius and Seychelles, but does not appear to extend to Polynesia. 



Heliotropium indicum, Linn. 



Heliotropium indicum, Linn.; Hook, f., Fl. Brit. Ind., iv. p. 152; Griseb., Fl. Brit. "W. Ind., p. 485; 



F. Muell., Syst. Census Austr. PI., p. 100. 

 Heliophytum indicum, DC. ; Miq., Fl. Ind. Bat., ii. p. 925. 



Lbtti. — An annual, now almost everywhere in the tropics. Heliotropium is a genus 

 of more than 100 species, which are generally diffused in the warmer regions of both 

 hemispheres, and extend into some temperate regions. 



CONVOLVTJLACE^. 

 Ipomcea angustifolia, Jacq. 



Ipomcea angustifolia, Jacq., Ic. PI. Rar., t. 317, not of Choisy ; Bentli., Fl. Austr., iv. p. 425; 



Hook, f., El. Brit. Ind., iv. p. 205. 

 Ipomica filicaulis, Blume ; Miq., Fl. Ind. Bat, ii. p. 603. 



Timor Laut. — An annual species widely dispersed in Tropical Asia, Africa, and 

 Australia. Miquel records it from the " tropische gewesten der geheele aarde," but we 

 have seen no American specimen. 



As now usually limited, Ipomcea numbers between 300 and 400 species, generally 

 diffused in warm regions, but very rare or quite absent in temperate and cold countries. 



Ipomoea vitifolia, Sweet. 



Ipomcea vitifolia, Sweet; Miq., Fl. Ind. Bat., ii. p. 607; Hook, f., Fl. Brit. Ind., iv. p. 213. 



Timor Laut. — Throughout India, except the dry north-west, from Sikkim, Assam, 

 Chittagong, and Burmah, southward to Ceylon and Malacca, and the Archipelago. 



