BRACHIOPOD COMMUNITIES 77 



species found in the area. G. albida has been recorded from intertidal 

 flats to 80 fathoms in other regions. 



Glottidia albida is a member of a very old group, the Lingulacea, 

 which dates back to the Cambrian, about 550,000,000 years. This species 

 has been found since the upper Eocene, about 40,000,000 years ago. The 

 living forms have been recorded from Monterey Bay, California, south 

 to Acapulco, Mexico. 



In order to have a better understanding of the ecology of the living 

 brachiopods in the Catalina area, an attempt has been made to record 

 their conspicuous animal associates. Most of the collections have been 

 made with a biological dredge which has yielded large numbers of animals, 

 although many of the small forms are lost through the mesh of the dredge. 



In addition to dredge hauls several quantitative samples have been 

 taken in this area with bottom-sampler grabs of known area coverage. 

 These are random samples whose location can be predetermined only as 

 to the geographic location of the sample. The following list represents 

 the animals taken in one such sample from an area of six square-feet in 

 36 fathoms olif the Isthmus of Catalina Island. The animals have been 

 identified as completely as is presently feasible. The numbers indicate 

 the number of individuals of that particular kind found in this single 

 sample. The list of animals is arranged phylogenetically and alphabetically 

 within each major group. 



Sample #2961-54; October 9, 1954; 0.4 mi SW of Ship Rock, Catalina Island; 

 33°-27'-52" NL, 118°-29'-53" WL; 36 fathoms; shell and sand bottom; 6 square 

 feet area. 



Protozoa 



several undetermined Foraminifera 



Porifera 



Leuconia heat hi (Urban) — 1 

 encrusting yellow sponge — 1 



Coelenterata 



Plumularia sp. — 2 colonies 

 Paracyathiis stcarnsi Verrill — 3 

 Acanthoptilum gracile Gabb — 8 

 anemones — 7 



Nemertea 



undetermined species — 4 



Aschelminthes 

 Nematoda sp. — 10 



Bryozoa 



Antropora tincta (Hastings) — 1 large colony 



Phoronida 



Phoronis sp. — 6 

 Brachiopoda 



Laqueus calif ornianus (Koch) — 3 



Terehratalia occidentalis (Dall) — 2 



