220 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 19 



cea are absent except for the barnacle, Scalpe/luni, attached to stiff tubes 

 of polychaetes. 



In deeper bottoms, sediments are silt and mud ; polychaetes continue 

 the most prominent, and occur with ophiuroids, echiuroids, sipunculids, 

 small solenogasters and coelenterates. The most conspicuous polychaetes 

 are Chloeia pinnata, Lumbrineris pallida, Spiophanes and Tharyx species, 

 together with onuphids and maldanids. Brissopsids are frequent, as well 

 as large echiuroids, Jrynchite, and nemerteans, Cerebratulus. Charac- 

 teristic animals in 195 fms are the large mud-tube polychaetes, Pista 

 disjuncta and Maldane sarsi, and a tubicolous ceriantharian. 



Specific diversity ranges from 25 to 129 in a sample, and numerical 

 count from 100 to 2448. Biomasses are moderately high, ranging to 

 840.0 grams for a sample measuring 0.16 cuft. 



The following stations, by depth, were useful in indicating the diver- 

 sity and kinds of species in the Palos Verdes area ; they are numbered 1 

 to 27 (see charts), with station (4801-57 to 4832-57) and serial number 

 (11 to 60) (see Map, vol. 19, p. 6). 



1. Sta. 4801 (no. 28). 0.3 mi offshore from Portuguese Point, in 7 

 fms. OPG took 1.0 cuft of organic debris, shelly silty mud and red algae. 

 In addition to species shown on the chart, the sample contained a small 

 anemone (1), nemerteans (10), four kinds of amphipods (20 speci- 

 mens), a Caprella ( 11 ), a tanaid ( 1 ), and a cumacean (2). 



Numbers of species and specimens were estimated at : 

 polychaetes 34* species, 381 specimens 



echinoderm 1 84 



mollusks 6 1 1 



crustaceans 7 34 



others 2 1 1 



Total: 50* species, 521 specimens 



The most conspicuous was Chaetopterus, followed by Diopatra and ju- 

 veniles of Dendraster. The most abundant were Tharyx marioni (91), 

 Dendraster sp. (84), Ophiodroinus pugettensis (56), with 20 or more 

 of each of the following: Chaetopterus variopedatus, Eupolymnia crescen- 

 tis and Halosydna brevisetosa. 



2. Sta. 4830 (no. 28). 2.5 mi from Pt. Vicente light, in 7 fms. OPG 

 took 0.95 cuft of fine olive-gray sand. The screenings contained large 

 numbers of Dendraster sp. and other animals. In addition to those shown 



