208 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



among which fruticose lichens are most abundant, often occur- 

 ing in such large quantities as to give a distinct color to the 

 vegetation. A few of the more xerophytic species of ferns, 

 as well as a number of herbaceous perennial plants, occur. 

 The annual herbaceous forms are rather in the minority as 

 compared with the perennials. The following list includes the 

 plants which are most common in this region. 



Adiantum concinnum Lantana peduncularis 



Bursera graveolens Lipochaeta laricifolia 



Castela galapageia Maytenus obovata 



Ceropteris tar tar ea Pisonia tloribunda 



Chiococca alba Polypodium lepidopteris 

 Cissampelos Pareira pectinatum 



Clerodendron molle squamatum 



Cordia galapagensis Psidium galapageium 



Hookeriana Psychotria ruHpes 



lutea Scalesia pedunculata 



Croton Scouleri var. brevifolius Telanthera echinocephala 



Doryopteris pedata Tillandsia insularis 



Erigeron tenutf alius Tourneforfia rufo-sericea 



Euphorbia viminea Trachypteris pinnata 



Gossypium barbadense Waltheria reticulata 



lonopsis utricularioides Zanthoxylum Fagara 



Moist Region 



The vegetation of the moist region is of a decidedly meso- 

 phytic character, all the xerophytic species which persist in the 

 transition region having disappeared, except in a few rare 

 instances. In these cases there may be an occasional straggler 

 from below, or conditions of soil or exposure are such that 

 mesophytic plants will not grow. In general this region is 

 characterized by the presence of large forests, made up for the 

 most part of trees of Psidium galapageium, Pisonia Horihunda, 

 and Scalesia pedunculata, which it seems well to call the 

 ''Scalesia forests." The undergrowth is often dense in these 

 forests, and is made up mostly of larger species than are found 

 in the two lower regions. Epiphytic ferns and orchids, as well 

 as several species of leafy hepatics, grow abundantly. Lianes 

 also abound, although belonging largely to a single species. 

 The mesophytic species of ferns are very common, and often 

 form brakes of considerable size. In general, the vegetation 



