Ammobroma, a New Genus of Plants. 51 



VI. — On Ammobroha, a New Genus of Plants, allied to 

 Corallophyllum and Pholisma. 



Bt John Toeekt. 

 Read June 2tth, 1864. 



This singular plant was discovered in the year 1S54 by the 

 late Col. Andrew B. Gray, in his survey and explorations for 

 ascertaining the practicability of constructing a southern rail- 

 way to the Pacific. It was found in abundance on a range of 

 sandhills near the head of the Gulf of California, and is not 

 known to occur elsewhere. 



A brief notice of the plant was given in a memoir by Prof. A. 

 Gray, entitled Plantm Novm Thurberianai, which was pub- 

 lished in the fifth volume of the Memoirs of the American 

 Academy of Arts and Sciences, in the year 1854. A full de- 

 scription was reserved for Col. Gray's complete narrative of his 

 expedition. Various causes have hindered the publication ot 

 this work, and as it is now doubtful whether it will ever make 

 its appearance, owing to the recent death of that gentleman, it 

 seems proper that one of the most interesting of the scientific 

 results of his labors should no longer be withheld. 



The following are the characters of the new genus, taken 

 from dried specimens presented to me by Mr. Gray, and from a 

 drawing made from the living plant by Mr. C. Schuchard, who 

 accompanied the expedition as draughtsman. 



AMMOBKOMA*, Torr. 



Calyx deeply 10-parted ; the divisions setaceous, plumose. Corolla 

 monopetalons, tubular-furmelform, somewhat plicate ; the border 6-lobed ; 



* From a/i//of, sand, and /?pco/«>f, food ; in allusion to its place of growth, and the 

 use made of the plant by a tribe of Indians. 



