116 PROCEEDINGS OP THE AMERICAN ACADEMY 



VIII. 



CONTRIBUTIONS FROM THE GRAY HERBARIUM OF HARVARD 

 UNIVERSITY, NEW SERIES. 



IV. NEW AND LITTLE KNOWN PLANTS COLLECTED 

 ON MT. ORIZABA IN THE SUMMER OF 1891. 



By Henry E. Seaton. 



Presented by B. L. Robinson, January 11, 1893. 



The descriptions of new species and notes upon a few other plants 

 of interest presented in this paper are based upon a collection made by 

 the author on Mt. Orizaba in July and August, 1891. Mt. Orizaba 

 in the State of Vera Cruz has been visited by a number of collectors, 

 and is among the best known regions in Mexico. This is especially 

 true of its lower slopes in the vicinity of the towns of Cordoba and 

 Orizaba. These regions, where the writer's first collections were also 

 made, are on the southeastern slope of the mountain at altitudes of 

 2,700 and 4,000 feet. Higher points were successively visited, until 

 the station of Esperanza was reached, on the southern slope of the 

 mountain and at an altitude of 8,000 feet. In this region seven of the 

 new species here described were discovered. The ascent of the peak 

 to an altitude of 14,000 feet was made on the western slope above 

 the town of Chalchicomula. The remaining new species were found 

 between 9,000 and 12,000 feet. 



Drs. J. M. Coulter and J. N. Rose have been so obliging as to de- 

 termine some of the Umbelliferse, and their descriptions of two new 

 species are herewith given. The notes upon the Grasses are kindly 

 furnished by Prof. F. Lamson-Scribner. Warmest thanks are also 

 due Dr. B, L. Robinson, for his ready assistance in many of the deter- 

 minations. 



Ranunculus geotdes, HBK. Pine woods, Mt. Orizaba, 11,000 ft., 

 August (no. 179). This species has been somewhat confused with 

 R. Hookeri, Schl., but is distinguished by its more simple habit, 

 smaller and merely 3-lobed or parted radical leaves, and slightly 

 narrower petals. 



