356 MOLLUSKS OF THE GALAPAGOS STEARNS. 



modified by the comparatively low tciiipcraturc of tlic sMnoiiiidiai;- sea. 

 The rain occurs between February and .Iimc, but is very irre.<;iil;ir, and 

 often there is none lor one or two years. In tli(> Uij^lier ])<)rtions ol'tlie 

 islands, about 000 feet, there is often ruin all the year. The /.one up 

 to between 500 and <»00 feet is nearly without rain; therefore the ui)per 

 rej;ion remains always j^reen, the lower is arid and barren. At the 

 edge of the sea various maritime plants occur and in sonu' of the bays 

 manuroves. etc. In ascending' the hills IVoiu t he shore the whole <;roun(l 

 in all directions is co\-ered with apparently withered bushes, but on a 

 closer examination it is found that these ])lants are mostly in bloom. 

 This brushwood .^rows up to a^ heii;ht of ."> or (! feet, rarely 10 feet, and 

 here and there are found Ah/oroha trees about 20 feet high, and also 

 sporadic Pal<»santos {(hii<(<'i<m)y the latter being the largest tree in the 

 lower region ; it reaches a height of ."^O feet and .'i feet in circumference. 

 On places which do not allow the growth of any other plant, the gro- 

 tesque, tree-like Opioitias and gigantic Cerem are found. The Cercus 

 is generally seen in the most barren s])ots. These cactuses give a very 

 characteristic appearance to this region, liesides these jdants there 

 are some fifty or sixty others, principally shrubby. Then conuvs an 

 intermediate zone, the vegetation indicating increased humidity; this 

 latter is included between the altitudes of about 050 and 000 feet, and 

 sei)arat<>s the dry and hunud regions. This internu'diate belt, between 

 L'OO and 300 feet in width, is still more covered with brushwood of a 

 withered api>carance. The cactuses disappear and a trailing tree moss 

 (r.s«c<f) becomes the characteristic feature, and is easily distinguished 

 from a distance by its Avhite color. When the high plateau above tiu' 

 000 foot line is reached the whole sceneiN' changes; a refreshing, moist 

 bree/,e comes from the coast ; the traveler is suriounded by green woods 

 and stands on nu'adows. These woods are piiiu'ipally of trees 'M) feet 

 high, of an Andean type, and the lloraof lycuador at an altitude of, say 

 10,00(> feet, is suggested at an elevation of only one tenth as great; 

 there is great resemblance to the small Taramo forests (d" the Andes, 

 notonlyinthe habits of the trees but also in the small plants which 

 cover tiie ground, and in the mosses and lichens which cover the trees. 

 The woods are free, without creeping itlants, making a passage easy; 

 small meadows occui', consisting nearly entirely of gra.sses and rushes 

 (('Upcracar). Above this wooded region another may be seen, which is 

 destitute of trees and covered only with a coarse, short grass, which 

 extends to fhe highest stnnmits of the islands. (I'hatham, Hood, Inde- 

 fatigable, and flames.) 



The descrii)tion of these various /ones is based on the conditions 

 found on Charles Island; it is said to be the saine on the others of high 

 elevation. From this it is evident that such islands as do not reach to 

 the hunud region, like Hood, Barrington, Tower, etc., show only the 

 arid state. 



