30 WEST AMERICAN SHELES 
somewhat flesh-colored. The common length of 
adult specimens is three or four inches. The range 
of this species is from central California to Brit- 
ish Columbia northward, and Idaho eastward. 
Returning to the sea once more, we first mention 
a remarkable new shell obtained a few years ago 
by Mr. and Mrs. Oldroyd, of Long Beach, Cal., 
from fishermen who took it alive from 25 fathoms 
of water in San Pedro Bay. It was named Atrina 
oldroydii, Dall, and we may eall it Oldroyd’s 
Pinna. In fact, it is the first Pinna found in this 
part of the world, although in some portions of the 
ocean these great ‘‘feather-shells’’ are common 
enough. The specimen in question is over nine 
inches long, pointed at one end, and broad above. 
Its color is almost black, while the inside is a dark 
olive gray, with some iridescence. The description 
was published in 1901. 
From a very large shell we turn to a very small 
one, one-eighth of an inch in length. It is white, 
oval, and shaped like a minute Pinna. It is named 
Philobrya setésa, Cpr., the Moss-lover, (Bryophila 
setosa). It oeceurs from Santa Barbara south- 
ward. 
The great family of the Mussels have elongated, 
dark-colored shells and most of them spin a byssus 
of strong threads by which they anchor themselves 
to a place of safety. Where the waves dash over 
the rocks and the white foam curls like flowing 
milk, there the mussels love to make their home. 
Moored by their strong cables they enjoy the rush 
of air and water and fear no danger. 
