28 



fe\v months. Destruction is nearly as rapid southward around the San F"rancisco 

 waterfront, but on the Oakland side is generally somewhat less rapid, unprotected 

 piling lasting from 18 months to three years. In the Oakland estuary the activity of 

 Limnoria is greater than that of Bankia, and piling is not destroyed in as short a 

 time as it is nearer the Golden Gate (fig. 13). From South San Francisco on the western 

 side of the Bay and Alameda on the eastern, there is, southward, a vast stretch of 

 shoreline enclosing the southern end of the Bay, which is its largest area. Industrial 

 activity of a kind which requires waterfront construction is very scanty, however, in 

 this southern area. There are, therefore, few structures from which the activity of 

 borers may be measured. On account of the much greater industrial importance of 

 the northern areas a complete study of the southern area was not attempted. Some 

 investigations, however, were carried as far south as the Dumbarton Cut-off. At the 

 plant of the Schaw- Batcher Company in South San Francisco, there was found an 

 attack by Teredo diegensis, a species of teredo not observed during this survey in the 

 northern part of the Bay area. This will be discussed in the biological section of the 

 report. 



In the northern area, including the lower course of the Sacramento River, Suisun 

 Bay, Carquinez Strait and the adjacent portions of San Pablo Bay, where the de- 



1-ij;, 14. L ntrealcd lcrr\ slip ten(ifr ])ik's in I arquinez .Mr.nt, dcstroved by Teredo in 1919. 



(5. P. Co. Photo.) 



struction since 1917 by the teredo has been so swift and so unusually severe, every 

 waterfront structure as far upstream as Antioch has been attacked by the teredo. 

 Following is a list of the more important structures which have suffered most severely 

 from the borers in that area: 

 Hercules 



Fernandez Wharf. 

 Hercules Powder Co. 

 Rodeo 



6-Minute Ferry. 

 Oleum 



Union Oil Co. 

 Selby 



American Smelting & Refining Co. 



