22 DB. ASA GKAT OK A GEKUS OF GENTIANEiE, 



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Helinus occurs as an abundant creeper on the face of sandstone 

 rocks. 



Jatro^lia curcas is a cliaracteristic road-side shrul) on the 

 highest part of the range, as also Mcus cunea on the embank- 

 ments of the road and ledges of rock. 



liubusjlavus, aJBcehneria, and a Tern (not found in the plains) 

 occur near water in the forest. 



Throuorhout these hills there is not much cultivation. Tea has 



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dry 



eoncl 



great trouble he has taken in assisting me to name my collection 



both 



before the Society some time ago. 



Characters of a new G-enus consisting of two Species of Parasitic 



Genfianece. By Asa GthIt, F. Hon. Mcmb. L.S. 



[Read November 5, 1868-] 



One of the two little plants here described was detected, between 



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twenty-five and thirty years ago, upon one of the IVIangs or 

 Mangsi Islands, north of the Ladrones, by the naturalists of the 

 American South- Pacific Exploring Expedition under Commodore 

 Wilkes. The other and very nearly related species was found in 

 Java by the late Mr. Lobb, and the specimens are in the Hook- 

 erian herbarium. They are interesting chiefly from the fact that 

 the parasitic Gentianece hitherto known are all American. The 

 Gentianece generally recognized as root-parasitic are all Tropical- 

 American, and constitute the genus Yoyria of Aublet, along with 

 the sections designated by Grisebach, which Miqiiel has, perhaps 

 on insufilclent grounds, proposed to distinguish as genera. It is 



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likely that the tw^o little plants of the Eastern United States 

 w^hich compose the genus Bartonia of Muhlenberg {CentaureUaj 

 Michx.) are likewise parasitic, being leafless and of a yellowish 

 hue ; and Obolaria, of the same region, may be suspected to be 

 partially parasitic, after the manner of certain Scropliularinece. 

 Both these genera, I may remark, were considered anomalous 

 from having the w^hole parietes of the ovary ovuliferous, until it 

 was ascertained that many Gentians, and notably those of thQ 

 United States, had the same peculiarity. 



EopuxLON, nov. gen. Gentiancariim parasiticarum. 

 Calyx 4-fidus, lobis triangulari-ovatis acutatis sestivatione imbri- 



