ZOB 



A BIOLOGICAL JOURNAL 



Vol. I. JULY, 1890. No. 5, 



FLORA OF THE CALIFORNIAN ISLANDS. 



BY T. S, BRANDEGEE. 



The flora of these islands is of much interest to botanists on 

 account of the variations from mainland forms, largely due of 

 course to isolation and the effect of insular climate. There are 

 some plants upon them that in the present state of our knowl- 

 edge appear to be endemic, but their numbejr has been much 

 exaggerated and will doubtless be continually lessened by the 

 collection of fuller material and by future exploration of the south- 

 ern mainland, much of which is still almost unknown. 



A difference in the specific names of plants does not necessarily 

 mean a great difference between the plants themselves. It may 

 mean great variation in structure and it may mean almost or quite 

 .none at all. 



^ It has been suggested that these islands are the remnants of a 

 western ''Atlantis." The botanical arguments in favor of the 

 theory are drawn principally from the flora of Santa Cruz Island 

 and consist mainly of: numerous new species; absence of Plata- 

 mis, Spirceuy Fragaria, Poie7itilla, Geum ; the rd^rliy oi Delphinium y 

 Ranunculus-, Ribes, TrifoHumy Rubles, Lo7iic€ray etc. 



The absence of the ^sycamore is easily accounted for — it loves 

 the rich alluvial lands bordering slow flowing streams, and the 

 canons of the islands sloping steeply to the sea offer no such 

 habitat. Spiraea, Fragaria, Potentilla and Geit^n are plants of cooler 

 regions, comparatively rare on the adjacent mainland and to the 

 south — the last, indeed, one would hardly expect to see mentioned 

 in connection with the islands. RantinculuSy Delphiniuvi and 7>7- 



foliti^n are about as abundant, in the proper season, as at any 

 place o\\ the southern mainland. Ribes fruiting freely and Loiii- 

 cera are fairly abundant and ^?/(5?/i on the. south side is plentiful 

 and luxuriant, often completely covering small oaks. 



