33^ Plcints of San Francisco, [zoe 



ones, are more or less in bloom during the whole year, the more 



r 



hardy annuals becoming perennial as is the case with Sonchus ale- 

 racetiSy Craphalhwi pitrpureimi^ Chenopodiian anibrosioides, etc. 



Dr. Behr records^ that there were some small conifers on 

 Lone Mountain as late as 1854. None are now to be found, and 

 very few trees of any kind worthy to be so called now exist. In 

 shaded places in the cemeteries and parks, Qiierciis agrifolia reaches 

 a diameter of two feet. Salix lasiolepis makes trees of considerable 

 size near the old Russ Gardens. Heteromeles arbutifoliay Myrica 

 Calif oryiica and Sanibitciis glaitca may possibly be included, for they 

 occasionally reach moderate dimensions. 



The Mediterranean and Chilian plants form in our flora a well 

 marked and often disputed element. Many of them are considered 

 indigenous plants, upon what seem to the writer very slender 

 grounds. San Francisco was a Spanish town for fifty years before 

 California was acquired by the United States. Its cattle, horses, 

 sheep, goats, came from Spain direcdy, or by the way of Mexico 

 and Chili. So did the seeds they planted in the ground. The 

 ships that brought supplies lay long in the harbor, which was then 

 at North Beach, and we find accordingly that if there is one spot on 

 the peninsula more blessed with Mediterranean weeds than any 

 other it is the vicinity of Black Point and the Presidio. There are 

 so many cases known where plants and insects brought by accident 

 or intent into a new region have overrun it with great rapidity, that 

 there is no special reason for astonishment at finding these plants 

 already well established. In their spread they were greatly aided 

 by the pastoral habits of the people, with their numerous flocks of 

 sheep and herds of catde, which covered the plains, and in seasons 

 of scarcity penetrated the mountains during the Spanish occupancy. 

 The direct comparison of our species with their nearest congeness 

 in other regions is but just begun and promises in its progress to 

 make important changes in our lists. 



The agency of sheep in disseminating plants is well known to 

 everyone. A case of the introduction of plants resulting directly 

 from the importation of wool may be seen just outside the gate of 

 the Reservation at Black Point. Immediately adjoining this en- 

 closure is the now disused Pioneer Woollen Mill. There grow in 



•Zoe, n, 3. 



