75 



August 2, 1854. 



Dr. D. H. Storer, Vice-President, in the Chair. 



The Chairman read a letter from Dr. WilHam O. Ayres, 

 of San Francisco. 



Dr. Ayres states that a species of Leuciscus, is not unfrequently 

 found in the markets of that city weighing twenty-five or thirty 

 pounds. The following items, relating to one of the huge trees 

 of California, derived from Dr. Bigelow, of San Francisco, were 

 also furnished by Dr. Ayres : " The tree lies on the ground, hav- 

 ing fallen many years since. From the base to the point where 

 it is broken off, it is found to he three hundred and ten feet ; all 

 beyond this was burned, probably by the Indians, but fragments 

 lie scattered along to the distance of a hundred and fifty feet, and 

 from the size of these fragments, Dr. Bigelow feels confident 

 the tree must have been at least five hundred feet high. At the 

 base it is, by estimation, one hundred and ten feet in circumfer- 

 ence, and at the end of the three hundred and ten feet men- 

 tioned above, it is by measurement forty feet in circumference. 

 This is almost as much beyond, in size, the great tree which has 

 attracted so much notice, as that is beyond trees of common 

 size." 



The Chairman also presented the following communica- 

 tion from Dr. Ayres : 



ON A METHOD OF PREVENTING THE RAVAGES OF THE " SHIP- 

 WORM." 



A plan for the preservation of submerged timber from the 

 attacks of the " Worm," has been devised by Mr. James G. Swan, 

 formerly of Boston, and now of Shoal Water Bay, W. T. He 

 claims that it is both cheap and effectual ; and having been ap- 

 pointed by the California Academy of Natural Sciences to inves- 

 tigate the matter, I wish to present to you the conclusions 

 reached by us. We find that a marine railway to which it was 

 applied, remains at the end of eighteen months perfectly sound, 

 while timber by its side, of the same species of wood, has 



