— 20 — 



To show a series of characteristic forms in a typical setting, Anaheim 

 Creek, a small intermittent stream emptying into San Pedro Channel 

 abont six miles sonth of Long Beach, will serve. Like most small 

 streams in this part of the coast, it ends in an intricate system of 

 sloughs in a marsh and finally empties into the ocean through an 

 enlarged lagoon-like portion al)out three-quarters of a mile in length 

 sheltered behind a long sand spit. This portion with some of the larger 

 connecting sloughs is shown in the sketch map (figure 18), which will 

 be found to differ from the condition shown on the usual maps because 

 of the changes occurring in such locations since the earliest surveys. 



IThe outer beaches on either side of the entrance are of sand slightly 

 coarser than that forming the extensive beach from which Long Beach 

 takes its name. South of the entrance, prolonging the sand spit 

 enclosing the lagoon and probal)ly formed by the same forces, is a 

 bar turning the entrance channel well to the north. The outer end 

 of this has been built up to some height and at certain stages of the 

 tide forms an island separated by a shallow channel from the tip of 

 the spit, though at the lowest tides it may be reached dry shod. 



On this bar-island and in less numbers on the north-west point may 

 be found some of the once far more abundant Pismo clam {Tivela 

 siultonvm). This form reaches a large size and has the stoutest shell 

 of any form from this region, eminently fitting it to stand the pounding 

 of the surf to which in these situations it is always exposed. But this 

 thick shell alone would not insure survival, as the sand is changing to 

 an extent that few persons reali/e, scoured out and deposited in 

 various ways and to dift'erent extents by the varying phases of the 

 tide and heights of the surf.* The siphons of this clam are short and 

 its feeding position is not farther from the surface than its own length. 

 Surf far less heavy than what is considered a "storm" often scours 

 out sand enough to dislodge the clam at this depth or deposits a layer 

 deep enough to bury it beyond reach of food. The clam is active, 

 however, and by constant burrowing down to escape erosion, or up to 

 reach the surface, maintains itself except in some of the heavier winter 

 storms when it may be washed out and piled up in numbers on the 

 higher beach too worn by the battering of the Avaves to dig in again. 



Curiously enough the only other form maintaining itself on these 

 exposed beaches is one with a thin and delicate shell, the razor clam 

 (Siliqua), which, though not obtained on Anaheim beach, ranges 

 throughout the state and was ol)served at Oceano. In this case the 

 powers of burrowing are astonishing. ]\Iany amateur diggers, seeing 

 a "neck" and failing to find even after prolonged digging the clam 

 to which it belongs, are prone to think that it has dug away. This is 

 usually a mistake as most adult clams can change their position only 

 very slightly and slowly. In the case of the razor clam it is, however, 

 entirely true that it "digs away" and if the first spade thrust does 

 not cut off its retreat and turn it out on the sand the chase is usually 

 a hopeless one. The elongated and slender form is well fitted for 

 passing through the sand and the muscular foot can be extended with 

 considerable force a distance of half the length of the shell and, 

 dilating near the tip, can obtain so firm a grip on the sand that the 



♦Thompson. The Spawning- of Uie Gninion. Fish Bulletin No. 3, California Fi.sh 

 and Game Commission. 1919. P. 15. 



