320 Wisconsin Academy of Sciences, Arts, and Letters. 



assavieum, Scaevola Plumieri, Sesuvium Portulacastnim, and 

 Vallesia glabra. The low sandy area back of the beach is cov- 

 ered in some places with a heavy growth of Sporobolus virgini- 

 cus, while in other places, where the sand is encrusted with salt, 

 Ipomoea Pes-caprae grows very abundantly and of great length, 

 individual plants sometimes being fully one hundred feet long. 

 Cyperus laovigatus is very common around the pools of brackish 

 water, which have a strong odor of Sulphurated Hydrogen. 

 Bordering this sandy area are low dense groves of Avicennia offi- 

 cinalis, Hippomane IMancinella, and Laguncularia racemosa. 

 There are several other low areas and ravines in the vicinity of 

 the shore, above high tide mark, which are filled with thickets 

 of Discaria paueiflora, and Parkinsonia aculcata. The remainder 

 of the lower part of the island at this place is covered with 

 bushes, Bursera trees, and cactus. Cereus sclerocarpus occurs 

 commonly in the vicinity of the shore but was not seen above an 

 elevation of 100 ft. Opuntia myriacantha, on the other hand, 

 occurs abundantly on the lower parts, and to a considerable ex- 

 tent to about 500 ft. At an elevation of 600 ft., however, it is 

 scarce, and much smaller than lower down. The specimens seen 

 at this elevation, were of about the same size as those which oc- 

 cur at an elevation of 350 ft. at Academy Bay a few miles west 

 of here. The Bursera trees are larger and more abundant above 

 an elevation of 350 ft. than they are lower down. They are* 

 usually heavily covered with fruticose lichens. Piscidia Ery- 

 thrina is another common forest tree in this region. 



There is a very noticeable decrease in the number of many 

 of the forms common on the lower parts, between 350 and 450 

 ft. elevation. Some of the species disappear here among which 

 are : Croton Scouleri, Discaria paueiflora, Maytenus obovata, 

 and Telanthcra echinocephala. A few stunted specimen of Cheil- 

 anthes microphylla were found in the lava crevices at an eleva- 

 tion of 350 ft., and were the first ferns ever collected on this 

 island. 



There are fewer trees in the region of the craters, at 400 ft., 

 elevation, than lower down, and the country is covered with 

 Lantana bushes four to five feet high with a few trees scattered 

 through them. The sides of the craters are covered with low 

 bushes of Euphorbia viminea, and other species, while at the 

 top there are bushes, ferns, and grasses. The country to the 

 north of these craters, is heavily forested with Bursera and 



