BOTANY. 295 



referred it to the fig-tree or the pomegranate. The plants which we 

 saw, in various places along the shores of the Dead Sea, resemble very 

 closely the milkweed, which is so common in the United States : it is, 

 in fact, a closely allied plant, being the Asclepias procera of the earlier 

 writers, now, however, forming part of the genius Calotropis. This 

 plant occurs in many parts of the East, and was known as early 

 as the time of Theophrastus. It is a tall, perennial plant, with thick, 

 dark green, shining, opposite leaves, on very short footstalks ; the 

 flowers are interminal, and have axillary umbels of a purple color, 

 containing numerous flattened, brown seeds, each furnished with a 

 silky plume or pappus. The bark, especially at the lower part of the 

 stem, is cork-like, and much fissured. If it be cut, or a leaf torn off, a 

 viscous, milky juice exudes, which is exceedingly acrid, and even caustic, 

 and is said to be used in Egypt as a depilatory. In Persia, this plant is 

 said to exude a bitter and acrid manna, owing to the puncture of 

 insects. Chardin says that it is poisonous. Both the plant and its 

 juice have been used in medicine, and probably are identical with 

 the mudar, or madar, of India, which has attracted so much notice as 

 a remedy for diseases of the skin. Condensed from Lynch? s Expedition 

 to the Dead Sea. 



ALPINE FLORA OF MOUNT WASHINGTON. 



THIS highest region [of Mount Washington] is characterized by an 

 assemblage of Alpine or arctic plants, and by a variety of mosses and 

 lichens specifically identical with those of Northern Europe. The flora 

 of the uppermost region of Mount Washington consists of species 

 which are natives of the cold climate of Labrador, Lapland, Greenland, 

 and Siberia, and are impatient, says Bigelow, of drought, as well as of 

 both extremes of heat and cold ; they are, therefore, not at all fitted to 

 flourish in the ordinary climate of New England. But they are pre- 

 served here, during winter, from injury, by a great depth of snow, and 

 the air, in summer, never attains, at this elevation, too high a tempera- 

 ture, while the ground below is always cool. When the snow melts 

 they shoot up instantly, with vigor proportioned to the length of time 

 they have been dormant, rapidly unfold their flowers, and mature their 

 fruits, and run through the whole course of their vegetation in a few 

 weeks, irrigated by clouds and mists. 



If we attempt to speculate on the manner in which the peculiar 

 species of plants, now established on the highest summits of the 

 White Mountains, were enabled to reach those isolated spots, while 

 none of them are met with in the lower lands around, or for a great 

 distance to the north, we shall find ourselves engaged in trying to 

 solve a philosophical problem, which requires the aid, not of botany 

 alone, but of geology, or a knowledge of the geographical changes 

 which immediately preceded the present state of the earth's surface. 

 We have to explain how an arctic Flora, consisting of plants specifi- 

 cally identical with those which now inhabit lands bordering the sea, in 

 the extreme north of America, Europe, and Asia, could get to the 

 top of Mount Washington. Now, geology teaches us that the species 



