92 THE NAUTILUS. 
In his checklist Dall merely states that it is found on the 
oyster beds of the Bay (Checklist of Recent Bivalve Mollusks of the 
N. W. Coast, p. 18, 1916). 
Packard (Univ. of Calif. Publ. Zool., Vol. 14, No. 2, p. 257, 
1918) states in his report on the mollusca obtained by the U. 8. 
Bureau of Fisheries Survey of San Francisco Bay that, ‘‘ Al- 
though it was not taken by the Survey it is reported to occur 
within the lower division of the Bay in sufficient numbers to be 
marketed occasionally.’’ 
The above is a review of all of the published records of the 
species on the west coast which are known to the writer. Mrs. 
Ida S. Oldroyd tells me she received specimens some years ago 
collected by Fred L. Button at Alameda. Henry Hemphill 
made wonderful discoveries during his extensive collecting on 
the eastern side of the Bay, among other things, the sand clam, 
Mya arenaria, but his collection does not contain a specimen of 
the plicated mussel from any west-coast locality. So it may be 
inferred that he did not find it. 
Its extensive spread in the bay region however cannot be 
doubted. Through Mr. R. A. Coleman the California Academy 
of Sciences recently received 18 beautiful specimens of this 
mussel. They were taken at Bay Farm Island about one mile 
south of Alameda on the eastern side of the Bay. They were 
found living on the mud flats in very considerable numbers at- 
tached to the roots of Spartina stricta maritima, determined by 
Miss Alice Eastwood, locally known as wild rice. It is said to 
be occasionally brought into the markets from this locality. 
Mr. Coleman states that the mussels were delicious eating. 
Many of the shells are over a hundred millimeters long and as 
much as fifty millimeters wide. The epidermis has a very high 
polish and the umbones have been only slightly eroded, in 
many cases none at all. 
Those persons anxious to learn how long it takes to develop 
a variety, subspecies or species may well keep watch of Modiolus 
demissus. 
