— 64 — 



Habitat and habits — This species is oftenest found in stiff blue 

 mud or clay in bays or in other partially sheltered places. If the 

 tunnels are in clay and hence not subject to shifting by the currents 

 they are common near the entrance to bays where the rush of the tides 

 keeps the clay bare of sand and mud. They also inhabit reefs of 

 suitable rocks even though exposed to strong surf. 



Use — All these borers are much esteemed as food and though 

 not observed in the markets are used to quite an extent locally, often 

 being obtained from the reefs by the use of a pick or bar. 



Distribution — Zirfaea is found along the entire California coast 

 in suital)le locations. It was obtained at Crescent City, from Elkhorn 

 Slough, Monterey, from the reefs south of Carpinteria, from the clay 

 banks of the sloughs of El Estero near Carpinteria, in the soft 

 bituminous rock cliffs between Goleta and Santa Barbara, and all the 

 reefs from Piedras Blaneas to Ventura (C. L. H.). It was found iu 

 Morro Bav. in the clav of Anaheim Slough and at the entrance of 

 False Bay (W). 



Parapliolas californica Conrad 

 Plate 19, figure 1 



Description — This species is said to reach a length of three or 

 more inches (Keep). The anterior end of the shell is roughened and 

 nearly round while the siphonate end is aliruptly smaller and ends in 

 soft epidermal scales. The hinge region is protected by two long 

 slender plates. 



Use and distribution — It is used without distinction along with the 

 other species of borers. It ranges from jMonterey south. Specimens 

 were obtained from the reefs at Point Sal, Point Conception, near 

 Carpinteria and north of Ventura (C. L. H.). 



Pholadidea pen'ita Conrad 

 Plate 19, figure 2 



Description — The anterior half of the shell is quite globular, the 

 siphonate end tapers to a slightly gaping extremity covered with 

 brownish epidermal scales. The accessory plate over the hinge region 

 is triangular. 



Use and distribution — This is found along the entire California 

 coast in suitable locations. What has been said of the use of the other 

 borers will apply here. 



